Balsamic-Roasted Portobello Steaks with Butter Bean Mash is a hearty and healthy vegetarian meal. Featuring portobello mushrooms in the most wildly flavorful marinade, and garlicky mashed butter beans as a fiber-rich substitute for potatoes. Sure to please both vegetarians and meat-eaters!
Why You'll Love these Portobello Steaks
This has to be one of the BEST plant-based recipes I have ever eaten. It was inspired by a recipe created by my favorite chef, Yotam Ottolenghi, in his most recent cookbook, Flavor. (Truly, can't recommend this cookbook enough!)
The combination of mega-meaty portobello steaks in an ultra-savory marinade, and garlicky butter bean mash is a match made in comfort food heaven. Steak and potatoes who?!
The key to mushroom success is to enhance their flavor with a umami-rich marinade that plays up the portobellos’ earthy flavor. And let me tell you, this one reigns KING. Even the most devout carnivores/meat-and-potato lovers can get down with this meal.
Add a crisp green salad on the side, or your favorite green veggie, and this meal is sure to impress.
Recipe Ingredients and Substitutions:
- Portobello Mushrooms: One of the things I love most about portobello mushrooms is their “meaty” factor. They really are a fantastic swap for red meat when roasted or grilled. For this recipe, you need 1 lb total, which amounts to 4 large or 6 medium caps.
- Olive Oil: You need a good amount of heart-healthy olive oil for this recipe. The fruity, grassy notes play up the earthy spices and meaty mushroom profile beautifully.
- Balsamic Vinegar: Look for a good-quality balsamic vinegar that's sweet and fruity with a good bit of sharpness to balance it out. And ideally one that's thick, yet not too syrupy.
- Maple Syrup: A little sweetener helps balance the sharpness of the vinegar. Maple syrup, in particular, has rich complex flavor notes that works especially well here.
- Tomato Paste: Hello, umami! Tomato paste adds tangy brightness to the mushroom steaks, plus helps thicken the marinade.
- Spices: A mix of smoked paprika, cumin, and oregano add earthy, smoky spice to the mix. You can also add garlic powder, garam masala, and chili powder, if you wish!
- Garlic: Garlic cloves are roasted with the mushrooms to deepen and sweeten their flavor. This creates the aromatic backbone for the butter bean mash.
- Butter Beans: Butter beans, or large lima beans, have a creamy texture and mild, almost-buttery flavor. (The small, pale green, kidney-shaped beans that you may recognize as lima beans are actually baby limas.)
Step 1: Marinate the Mushrooms
In a medium bowl, combine ⅓ cup olive oil, balsamic vinegar, maple syrup, tomato paste, smoked paprika, cumin, oregano, salt, and pepper; whisk to combine.
Place portobello mushrooms in a 13x9-inch baking dish. Pour marinade over mushrooms, and toss to ensure it coats both sides. Place garlic cloves in a piece of tin foil, and cover with 1 tsp. olive oil. Loosely wrap the foil over garlic, and place in the corner of the baking dish with mushrooms.
Let mushrooms sit at room temperature while you preheat the oven to 425ºF.
Step 2: Bake the Mushrooms and Garlic
Place pan in the preheated oven and bake, uncovered, for 15 minutes. Remove from oven, and gently flip portobello mushrooms. Loosely tent the pan with foil, and place back in the oven for 15 more minutes (30 minutes total).
Step 3: Blend Butter Beans
Meanwhile, place butter beans, broth, Parmesan or nutritional yeast, melted butter or oil, and salt in the bowl of a food processor.
Remove pan from the oven, and turn off heat. Unwrap the garlic cloves, and transfer garlic plus any residual oil to the food processor with butter beans. Place foil tightly back over the pan of mushrooms, and place back in the oven to keep warm.
Blend the butter bean mixture until smooth and creamy.
Step 4: Cook Butter Bean Mash
Transfer mashed butter beans to a medium saucepan. Cook over medium heat, stirring often to prevent sticking, until warmed through. Remove mushrooms from the oven.
Step 5: Serve Portobello Steaks over Butter Bean Mash
Divide butter bean mash evenly between 3 plates, and top with balsamic-roasted portobello steaks. Drizzle any residual oil in the pan overtop, and garnish with fresh thyme.
What to Serve with Portobello Steaks:
All this meal really needs a veggie side dish. Here are some of my favorites:
- Broccoli: My 15-minute Perfect Sautéed Broccoli recipe is a reader-favorite, goes-with-anything side.
- Brussels Sprouts: The flavor of these Crispy Brussels with Maple-Mustard Glaze will be an absolutely delicious complement to the mushrooms.
- Salad: You also can't go wrong with a crunchy green salad. This Shaved Brussels and Pear Salad is light and crisp with a fantastic lemon-Dijon dressing.
How to Store and Reheat:
- Store: Store mushrooms and butter bean mash separately in air-tight containers. Refrigerate for up to 4 days.
- Reheat: Both the butter bean mash and portobello mushrooms reheat best in the oven. Spread the butter bean mash in a small 8x8-inch baking dish, and stir in an extra splash of broth to help rehydrate. Add mushrooms to the pan (either right on top of the mash, or to the side), cover with foil, and bake at 350ºF until warm.
More Top-Rated Mushroom Recipes to Try:
If you give these portobello steaks a try, snap a pic and tag #dishingouthealth on Instagram so I can see your beautiful creations. I also really appreciate readers taking the time to leave a rating and review! Lastly, follow along on Facebook and Pinterest for the latest recipe updates.
Balsamic-Roasted Portobello Steaks with Butter Bean Mash
- 13x9-inch baking dish
- Food processor
- Small saucepan
- ⅓ cup extra-virgin olive oil
- 3 Tbsp. balsamic vinegar
- 1 Tbsp. maple syrup
- 1 Tbsp. tomato paste
- 1 tsp. smoked paprika
- 1 tsp. ground cumin
- ¾ tsp. dried oregano
- ½ tsp. each kosher salt and black pepper
- 1 lb. portobello mushroom caps, wiped clean (about 4 large or 6 medium)
- 3 garlic cloves
- Fresh thyme leaves for garnish
Butter Bean Mash
- 2 (15.5-oz.) cans butter beans, rinsed and drained
- ⅓ cup plus 1 Tbsp. vegetable broth
- 3 Tbsp. grated Parmesan cheese (sub nutritional yeast)
- 2 Tbsp. melted butter (sub vegan butter or olive oil)
- ½ tsp. kosher salt
- Prepare mushroom marinade: In a medium bowl, combine ⅓ cup olive oil, balsamic vinegar, maple syrup, tomato paste, smoked paprika, cumin, oregano, salt, and pepper; whisk to combine.Place portobello mushrooms in a 13x9-inch baking dish lightly coated with cooking spray. Pour marinade over mushrooms, and gently toss to ensure both sides are well-coated. Place garlic cloves in a small piece of tin foil, and cover with 1 tsp. olive oil. Loosely wrap the foil over garlic, creating a ball, and place in the corner of the baking dish with mushrooms. (This helps the garlic roast without burning.)Let mushrooms sit at room temperature while you preheat the oven to 425ºF.
- Place pan in the preheated oven and bake, uncovered, for 15 minutes. Remove from oven, and gently flip portobello mushrooms. Loosely tent a piece of tin foil over the pan, and place back in the oven for another 15 minutes (30 minutes total).Meanwhile, prepare Butter Bean Mash: place butter beans, broth, Parmesan or nutritional yeast, melted butter or oil, and salt in the bowl of a food processor.
- Remove pan from the oven, and turn OFF heat. Unwrap the garlic cloves, and transfer garlic plus any residual garlic oil to the food processor with butter beans. Place foil back over the pan of mushrooms, and place back in the oven to keep warm.Blend the butter bean mixture until smooth and creamy, stopping to scrap down the sides as needed.
- Transfer mashed butter beans to a medium saucepan lightly coated in cooking spray. Cook over medium heat, stirring often, until warmed through. Remove mushrooms from the oven.Divide butter bean mash evenly between 3 plates, and top with roasted portobello mushrooms. Drizzle any residual oil in the pan overtop, and garnish with fresh thyme.