Instant Pot mushroom Bolognese is a decadent vegan sauce that treats you to mouthfuls of savory, rich flavors. Easily make the sauce everyone will rave about in the Instant Pot or on the stovetop too.

There are a few flavor combinations with this one that might appear random. But make no mistake – everything is intentional. As much as I love tossing things in my Instant Pot, lifting the lid in anticipation, and discovering what I’ve concocted, I love being intentional and knowing how rewarding the first dip of the spoon will be.
That’s what this sauce is all about.
Ingredients
Don’t let the list of ingredients intimidate you. Once you prep the onion, carrots, celery, and mushrooms, this recipe is a breeze.
My advice?
Crank up the tunes, sharpen your chef's knife, and in less than 20 minutes (including dancing pauses), you’ll be ready to roll.
Mushrooms – Brown chestnut mushrooms (kin to white button mushrooms) work well for this sauce; however, so will the white variety. As a guide, I've used anywhere from 20-25 mushrooms, which amounts to 5 ½ cups chopped.
Avoid washing the mushrooms in water. If you want to clean them, use a clean cloth or paper towel and wipe them. You can also use a soft brush. Mushrooms will absorb extra water, and this will reduce their flavor and dilute your final cooking product.
Onion – 1 medium yellow onion, diced small or about 1 cup.
Carrot – 1 medium-large carrot, diced small (¾ cup). Carrots natural sweetness, and I use them often with tomato-based sauces because they enhance the sugar in tomatoes.
Celery – 2 stalks of small-diced celery should yield about 1 cup. Don’t get too caught up in precise measures. If it’s slightly more or less, you will still have a delicious sauce.
Fennel – When building the initial flavor base with the mushrooms, onions, carrot, and celery, adding 1 tsp. of fennel seeds brings out the mushroom flavor. Adding it at the beginning will soften the seeds and release their flavor.
Garlic – 4 cloves, minced or pressed.
Vegetable broth – I used vegetable broth to deglaze the Instant Pot after sauteing the veggies. Depending on how much moisture the mushrooms hold, you may not need to deglaze. Add it anyway because it will give you an extra cup of liquid that cooks with the tomatoes.
Walnuts – 1 cup of chopped walnuts creates a meaty texture for this hearty sauce. Walnuts are resilient. They retain most of their toothy mouthfeel even after pressure cooking or a long stovetop simmering.
Soy sauce – The umami flavor of soy sauce mingles with the mushrooms and enhances their earthy flavor. I find a darker soy sauce or tamari adds the best flavor.
Balsamic vinegar – Thick balsamic vinegar adds a subtle sweetness complementing the tomatoes. In particular, it subdues any sharpness of the tomato paste.
Marmite – Even if you don’t love spreading it on your toast, marmite the salty and super-umami yeast extract is my ingredient for this sauce.
It said that marmite is a 'love it or hate it' food, but I disagree slightly. While I would never spread this salty, yeasty ingredient on toast, it adds a unique flavor to the sauce. You always have the option of adding half the amount, tasting after cooking, and then stirring in another spoonful if you like where the flavor is going.
Tomato paste – Although we’ll be cooking this sauce down substantially, you still want the concentration of tomatoes. Tomato paste is, frankly, the best way to achieve this. As I tested this recipe, I finally arrived at ¼ of a cup (4 tablespoons). That’s the sweet spot.
Oregano – Dried oregano is the only dried herb you’ll find here. In the past, I’d be tempted to add a slew of dried herbs, but you don't need to over-season this dish in that way. Oregano is all you need.
Red chili flakes – Cut through the savory just enough by adding a few red chili flakes. My preference is to add 1 teaspoon. If you don’t like your sauce spicy, add ½ a teaspoon, and after you pressure cook, you can adjust with more.
Tomatoes – Aim for canned tomatoes in juice. Use a big can (28 oz.) or 2 15-oz. cans.
If you use whole tomatoes, be sure to break them up before adding them. If you use a stick or immersion blender straight into the can to break them up, do that in the sink. Do I need to say more about scraping tomato off the walls?
Pro Tips
- Use a 6-quart or larger Instant Pot for this recipe.
- Allow the Instant Pot to heat on High Sauté before adding the mushrooms, onions, carrots, celery, and fennel. Adding vegetables to a cold pot can result in the vegetables sticking to the bottom as it begins to heat.
- Some mushrooms will release a lot of moisture as they cook. The best remedy is to simply sauté them for longer. Be sure to stir them so that they and the rest of the veggies don’t stick. You want to allow at least 5 minutes for the initial sauté, but keep it going for 10 minutes or longer if you need to. Any extra mushroom liquid will not compromise the flavor of the sauce. You don’t need to drain it off. You may, however, decide not to add the ½ cup of vegetable broth if there is a lot of it.
- Keep the Instant Pot on SAUTE as you add the rest of the ingredients, be sure to stir everything well before and after adding the tomatoes.
- I used a manual release of the steam handle, but you can also let it naturally release for 20 minutes. The sauce will continue to reduce as the steam releases.
- Once you lift the lid and stir the sauce, if you want it thicker, set the Instant Pot on High Simmer and allow it to continue cooking. The longer you cook the sauce, the more it will reduce.
- If you are serving the sauce immediately after cooking, start the pasta once you set the Instant Pot to High Pressure. That should be enough time to boil the water and cook the pasta.
Stovetop directions
- Use a heavy-bottomed pot to make the sauce. Heat the pot to medium heat, then add the mushrooms, onions, carrots, celery, and fennel. Simmer the ingredients until the mushrooms have released their moisture.
- Deglaze the pot, then add the remaining ingredients. Be sure you mix everything well. Bring the sauce to a slow simmer, then cover the pot. Simmer the sauce for 1 hour. Check it a few times to ensure that it doesn’t need more broth.
- Uncover the pot and stir the sauce. If you want it further reduced, simmer it for longer.
What to serve with Bolognese sauce
The most obvious is pasta! Bolognese is a hearty sauce that is compatible with robust types of pasta. Consider tagliatelle, pappardelle, fettuccine, or tube shapes such as rigatoni and penne. We always opt for whole wheat, vegan pasta. Be sure to check the labels if you aim to go in this direction.
Fresh basil leaves chopped or torn add a bright, herby flavor to Bolognese sauce. We usually reserve this as a garnish. If you add it to the sauce, do so at the end of cooking. Fresh basil is delicate and does not stand up to pressure cooking very well.
Vegan parmesan – Hello, baked hemp seed parmesan! That’s our favorite, and we highly recommend it. You can make this addictive condiment while the sauce cooks and be ready for sprinkle madness!
Common Questions
The best substitute for marmite is vegemite. Both are vegan and have similar, although not identical, tastes. Miso paste, in the same amount, is another worthy and more accessible substitute. Nutritional yeast can also be used in a pinch.
Ground fennel is the best option. Use ½ the amount of the seeds as the ground version has a more condensed flavor. Caraway, anise, or dill seeds are the best substitute for vegan Bolognese sauce.
Canned tomatoes, because they have already been cooked and condensed, will yield a dark, thick, and rich sauce. Use diced or crushed tomatoes that are packed in juice. If you use whole tomatoes, break them up before adding them to the sauce.
Yes. Place the sauce in a durable freezer container or heavy freezer bags and freeze them for 3-4 months. Freeze the sauce without the pasta because the pasta can get soggy after it thaws.
Recommended Pasta Recipes
Instant Pot mushroom Bolognese
Instant Pot mushroom Bolognese is a decadent vegan sauce treating you with mouthfuls of savory, rich flavors that everyone will rave about.
- Prep Time: 30 min
- Cook Time: 40 min
- Total Time: 1 hour 10 minutes
- Yield: 8 servings 1x
- Category: pasta
- Cuisine: Italian
- Diet: Vegan
Ingredients
- 1 lb. (453 gm.) chestnut or button mushrooms (5 ½ cups chopped)
- 1 medium yellow onion, diced small
- 1 carrot, peeled and diced (¾ cup)
- 2 stalks of celery, diced small (1 cup)
- 1 tsp. fennel seeds
- ½ cup of vegetable broth
- 1 cup of chopped walnuts
- 4 cloves of garlic, peeled and minced or pressed
- 3 Tbsp. soy sauce
- 3 Tbsp. balsamic vinegar
- 2 tsp. marmite (see notes for substitutions)
- ¼ cup tomato paste
- 2 tsp. oregano
- 1 tsp. red chili flakes
- 1 - 28 oz. (800 gm.) can diced tomatoes, packed in juice
- Fresh basil leaves for a garnish (optional)
Instructions
Instant Pot
- Heat the Instant Pot on HIGH SAUTE, then add the mushrooms, onions, carrots, celery, and fennel seeds.
- Sauté the vegetables for 5 – 10 minutes until the mushrooms release their moisture. Stir occasionally.
- Deglaze with ½ a cup of vegetable broth. Stir the bottom of the Instant Pot so that any bits on the bottom are released.
- Add the walnuts, garlic, soy sauce, balsamic vinegar, marmite, tomato paste, oregano, and chili flakes. Stir well.
- Stir in the tomatoes the cancel the SAUTE process. Secure the lid, and close the steam release handle. Set the Instant Pot to HIGH PRESSURE for 20 minutes.
- If you are serving the sauce over pasta, start the water now.
- Once cooking has finished. Carefully release the steam release handle. Once the float valve is down, carefully remove the lid.
- Stir the sauce. If you want it thicker, set the Instant Pot to HIGH SAUTE and cook it for 5-10 more minutes until you have a consistency you like. This is also a good time to taste the sauce and adjust any of the flavorings.
- Serve over pasta and garnish the sauce with fresh basil or baked hemp parmesan if desired.
Stovetop Instructions
- Heat a heavy-bottomed pot over medium heat. Add the mushrooms, onions, carrots, celery, and fennel seeds. Sauté the vegetables for 5-10 minutes, stirring them often until the mushrooms have released their moisture.
- Deglaze the pot with ½ a cup of vegetable broth. Use a wooden spoon to pick up any bits of vegetables that have stuck to the bottom.
- Add the walnuts, garlic, soy sauce, balsamic vinegar, marmite, tomato paste, oregano, and red chili flakes. Mix everything well.
- Add the tomatoes, mixing them with all the ingredients. Bring the sauce to a slow simmer, cover the pot, and simmer the sauce for 1 hour or until the sauce is reduced and thick.
- Uncover and continue simmering until you have a consistency you like.
Notes
- This recipe is intended for a 6 quart or larger Instant Pot.
- The best substitute for marmite is vegemite, miso paste, or nutritional yeast.
- Be sure not to wash the mushrooms in water. They will soak up added water which will diminish their flavor. To clean them, use a soft cloth, paper towel, or soft brush.
- Bolognese sauce freezes really well. I don't recommend freezing it with pasta mixed in because the pasta can get soggy once thawed.
- If you do not have fennel seeds, substitute with ½ a teaspoon of ground fennel.
Keywords: Instant Pot mushroom Bolognese
MJ
It is a myth that mushrooms absorb water. https://www.epicurious.com/archive/blogs/editor/2008/09/cleaning-mushro.html
Denise
Interesting mushroom debate on this thread. There certainly a lot of perspectives. Thanks for sharing this.