This Vegetarian Portobello Pot Roast recipe can be made easily in the slow cooker or Instant Pot (pressure cooker). And it’s SO hearty and comforting and delicious!
As a Midwestern girl through and through, I’ve gotta admit, I will always love me a good pot roast. But hey, whoever said that had to include roast beef?
A few weeks ago, when I found myself with two leftover cartons of baby bella mushrooms in the fridge that needed to be used up stat, I decided to try swapping them in as the main ingredient in my traditional pot roast recipe. And lo and behold, they turned out to be a plant-based swap made in heaven. This vegetarian pot roast recipe was a total winner!
It’s still full of those classic savory flavors (and garlicky gravy) that we all love. It’s quick and easy to prep, and easy to make either on the stovetop or in the slow cooker or Instant Pot. It’s naturally vegetarian and vegan. And it’s totally, wonderfully delicious.
My kind of comfort food.
To make the recipe, start by gathering lots of your starring ingredient — portobello mushrooms. You’re welcome to use full-size portobellos if you’d like. Or, you can be like me and just use a few cartons of baby bellas. Chop them up into bite-sized pieces…
…then combine them in a slow cooker or pressure cooker, along with some potatoes, carrots, pearl onions, garlic, and all of the ingredients for that classic savory gravy. Cook until the potatoes are nice and tender. Then for a final step, thicken that gravy up a notch…
…and voila! This delicious veggie-filled mushroom pot roast will be yours to serve and enjoy!
I went old-school and served mine over some egg noodles, but some grains or rice would also work well here. I served mine up with this simple salad and some red wine, and the meal was perfection.
Vegetarian twist for the win!
Vegetarian Portobello Pot Roast
Ingredients
- 1.25 pounds Yukon gold potatoes, cut into bite-sized pieces
- 1 pound baby bella mushrooms (if they are large, cut them in half)
- 2 large carrots, peeled and cut into bite-sized pieces
- 2 cups frozen pearl onions*
- 4 cloves garlic, peeled and minced
- 3 sprigs fresh thyme
- 3 cups vegetable stock, divided
- 1/2 cup dry red or white wine
- 3 tablespoons tomato paste
- 2 tablespoons vegetarian Worcestershire sauce*
- 2 tablespoons cornstarch
- Kosher salt and freshly-cracked black pepper
- optional garnish: finely-chopped fresh parsley
Instructions
Slow Cooker Method:
- Add potatoes, mushrooms, carrots, onions, garlic, thyme, 2.5 cups vegetable stock, wine, tomato paste and worcestershire together in the bowl of a crock pot, and gently toss to combine. Cook on low for 6-8 hours, or on high for 3-4 hours, until the potatoes and carrots are tender.
- In a separate bowl, whisk together the remaining 1/2 cup vegetable stock and cornstarch until combined. Add to the roast mixture, and gently toss to combine. Continue to cook for 1-3 minutes, until the sauce thickens up a bit.
- Serve immediately, garnished with fresh parsley if desired.
Instant Pot Method:
- Add potatoes, mushrooms, carrots, onions, garlic, thyme, 2.5 cups vegetable stock, wine, tomato paste and worcestershire together in the bowl of a pressure cooker, and gently toss to combine. Close lid securely and set vent to “Sealing”.
- Press “Manual”, then press “Pressure” until the light on “High Pressure” lights up, then adjust the up/down arrows until time reads 20 minutes. Cook. Then let the pressure release naturally, about 15 minutes. Carefully turn the vent to “Venting”, just to release any extra pressure that might still be in there. Remove the lid.
- In a separate bowl, whisk together the remaining 1/2 cup vegetable stock and cornstarch until combined. Add to the roast mixture, and gently toss to combine. Continue to cook for 1-3 minutes, until the sauce thickens up a bit.
- Serve immediately, garnished with fresh parsley if desired.
Notes
Did you make this?Let me know how it turned out in the comments below!
Fair recipe. The instant pot directions are missing when to add tomato paste, mushrooms should all be cut in half at least, keep potato pieces fairly large, add frozen peas once it’s cooked, and pressure should be released after 15 minutes of natural release to avoid mushiness.
no tomato paste in the instant pot version?
how much does all of this cost
Does this freeze well?
Hi. Potatoes don’t freeze very well. They become grainy and mealy when defrosted. I’ve tried a few times myself with bad results. You might want to decrease the recipe if you can’t finish it all in a week.
I double checked on Google and they confirmed it.
Stay healthy
Tried this out today for something warm and cozy. Made a few changes as ingredients were limited (especially during this crazy time). Used sliced fresh yellow onions, frozen sliced carrots, used dried basil and parsley, and instead of cornstarch I used unflavored pea protein powder. Which not only thickens it up but ups the protein. And served it with chickpea pasta. It was delicious!!
Hi! I don’t have any extra cooking machinery, could I attempt this on a stove? I’ve never used an instant pot or slow cooker and I’m not sure how to change the cooking times or method! Thanks for any help
Pea protein powder? Could you taste it ?
Nutrition Facts
Serving size: 1 cup
Servings: 7
Amount per serving
Calories 90
% Daily Value*
Total Fat 1.1g 1%
Saturated Fat 0.9g 5%
Cholesterol 0mg 0%
Sodium 338mg 15%
Total Carbohydrate 17.6g 6%
Dietary Fiber 2.6g 9%
Total Sugars 4.9g
Protein 3g
Vitamin D 0mcg 0%
Calcium 27mg 2%
Iron 1mg 6%
Potassium 626mg 13%
I see where the ingredients list says 6 cups vegetable broth divided…then only 2.5 cups added to the crock pot plus the other half cup to mix with cornstarch. When do you use the other 3 cups of vegetable stock? Am I missing something?
I see now that the recipe has been changed to 3 cups…Thanks!
I made this for dinner tonight and appreciate the recipe! The wine made the stew a little too bitter, so I added some butter to balance it out. I also found the stew bland for my taste, so I added some extra seasonings. Helped the flavor out alot. Overall, I am glad that I tried it:)
Do you have nutrition information available?
This was delish! Made it last night (Instant Pot version) and was extremely hopeful that the results tasted as good as it looked. I was not disappointed in the least. Reheated it for lunch today. Definitely a 5-Star keeper even with me forgetting the wine, Worcestershire and tomato sauce and using “Better than Bouillion Organic Chicken Base” in lieu of vegetable stock. Next time, I’ll add missing ingredients as well as chopped bell peppers and celery sauteed along with the onions. Believe me, whatever you’d add to your pot roast can be added to this. You won’t be disappointed either nor will you miss the meat.
I’ve tried making this several times, and every time it comes out VERY different than the picture. (Doesn’t everything”)
Our sauce seems so much thinner than what is pictured and everything comes out mushy when cooking exactly as the recipe suggests for the InstantPot. Tonight, I tried cooking at 14 minutes instead of 20, and it’s better but still mushy. I really don’t know what I’m doing wrong. I was really looking forward to this. Maybe I’m expecting too much of myself. The flavor is good, albeit a little bland. But overall, the dish is delish.
Ours also came out very different than the picture – thin sauce (almost like soup). The potatoes and carrots were super soft, but the mushrooms still had a bite. Flavours were blander compared to what we’re used to, but since we’re also making this for baby, it’s in a way perfect. Had to split it in 2 batches to do it in our 6qt Instant Pot. Next time, we’ll keep 1 batch the same for baby and experiment with different spice/herb combos for the other batch. All in all, it’s a great basic veggie loaded recipe that we’ve been needing.
I don’t feel like this recipe works very well for the instant pot unfortunately. The flavors were kinda underdeveloped, the sauce was thin even with the addition of cornstarch, the potatoes were mushy.. I could see it being better in the slow cooker maybe. Gonna try another recipe next time.