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
- Prep Time: 10 minutes
- Cook Time: 240 minutes
- Total Time: 250 minutes
- Yield: 6 -8 servings 1x
Description
This vegetarian Portobello Pot Roast recipe is quick and simple to prep, easy to cook in the Instant Pot or slow cooker, and it’s full of the classic savory flavors we all love!
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
Onions: Feel free to sub in sliced white onions, if pearl onions are not available.
Worcestershire: If making this recipe vegetarian, be sure to use vegan Worcestershire sauce.
***Cook time listed above is for a slow cooker set on “high”.
I made this dish for a meal train. I used vegan creamy vegetable stock instead of regular vegetable stock, fresh pearl onions instead of frozen and I added a little more garlic. The flavor was really good and the vegetables were perfectly cooked. I will make it again for my family with a few changes. I would NOT use the vegan creamy vegetable stock again because the appearance of the sauce was so unappetizing. Also, I would increase the amount of mushrooms to 1.5 or 2 pounds. Here is what I did to thicken up the sauce: I placed the 1/2 cup stock and corn starch in a medium/small sauce pan (do not turn on). Once the InstaPot was vented, I poured the liquid from the InstaPot into the sauce pan. Turned on the burner under the saucepan and heated it until it reached my desired thickness (stirring constantly). Then, I poured it back over the vegetables. Yummy!
Very easy to make. My guests and I loved it. Amazing flavor!
What can I use as a substitution for the Worcestershire sauce?
I am new to vegetarian and finding replacements for those favorite comfort foods has been a challenge. Thistle recipe was spot on, thick gravy, plenty of veggies, very filling. Made in instant o, so simple. This will for sure go into the rotations.
I just cooked on stove top for about 2 hours. Got rave reviews. I didn’t have worchestersire sauce but used Pick-a-Pepper.
I made this in a slow cooker. It came out very soupy and just tasted bitter and not savory. I won’t make this again.
I had the same experience as a few others, the sauce turned out thin. I added about 1/3 cup of nutritional yeast which thickened it right up
Made this last night. We are omnivores – We LOVED this meal. Definitely a do again in our household
OMG this is incredible. Even my 15 year old non-vegan was asking for more. Hearty and delicious! Make some great bread, ad something green like a salad and you are in business! Will definitely make this again and again1
Definitely good for something different. I did feel like a missed the meat a tad bit. Might make it again using a small amount of beef and a little less liquid. I subbed broth for the wine since I have young kids.
As one of the posters suggested, I did hit the saute button on my instant pot to help thicken it. It was a little soupy. My veggies were cut small and a little overcooked so I also might cook a little less next time.
Thanks for sharing.
Followed instructions EXACTLY. Turned out very bland and watery. Would not recommend at all. Very disappointed.