Portobello Pot Roast (Vegetarian!)

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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, guys!

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 ★ ★ ★ ★ ★ 4.5 from 41 reviews Prep Time: Prep Time: 10 minutes

Cook Time: Cook Time: 240 minutes

Total Time: Total Time: 250 minutes

Yield: Yield: 6 - 8 servings 1 x Print Pin 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! Scale 1x 2x 3x Ingredients 1.25 pounds Yukon gold potatoes, cut into bite-sized pieces

pounds Yukon gold potatoes, cut into bite-sized pieces 1 pound baby bella mushrooms (if they are large, cut them in half)

pound baby bella mushrooms (if they are large, cut them in half) 2 large carrots, peeled and cut into bite-sized pieces

large carrots, peeled and cut into bite-sized pieces 2 cup s frozen pearl onions*

s frozen pearl onions* 4 cloves garlic, peeled and minced

cloves garlic, peeled and minced 3 sprigs fresh thyme

sprigs fresh thyme 3 cup s vegetable stock, divided

s vegetable stock, divided 1/2 cup dry red or white wine

dry red or white wine 3 tablespoon s tomato paste

s tomato paste 2 tablespoon s vegetarian Worcestershire sauce*

s vegetarian Worcestershire sauce* 2 tablespoon s cornstarch

s 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”.