Keto Philly Cheesesteak Mushrooms (Printable Version)

Portobello mushrooms filled with savory steak, peppers, and melted cheese—a delicious low-carb main dish.

# Ingredient List:

→ Mushrooms

01 - 4 large portobello mushroom caps, stems and gills removed
02 - 2 tablespoons olive oil
03 - 1/4 teaspoon salt
04 - 1/4 teaspoon black pepper

→ Filling

05 - 1 pound thinly sliced ribeye steak or sirloin
06 - 1 tablespoon olive oil
07 - 1 small yellow onion, thinly sliced
08 - 1 small green bell pepper, thinly sliced
09 - 1 small red bell pepper, thinly sliced
10 - 2 cloves garlic, minced
11 - 1/2 teaspoon salt
12 - 1/4 teaspoon black pepper
13 - 1/2 teaspoon smoked paprika, optional

→ Topping

14 - 1 cup shredded provolone or mozzarella cheese

# Directions:

01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - Brush mushroom caps on both sides with olive oil. Sprinkle with salt and pepper. Place gill-side up on prepared baking sheet and roast for 10 minutes.
03 - While mushrooms roast, heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add onion and bell peppers; sauté for 4 to 5 minutes until softened.
04 - Add garlic and cook for 1 minute. Push vegetables to the side of the skillet.
05 - Add sliced steak to skillet and season with salt, pepper, and smoked paprika. Cook, stirring, until just browned, about 3 to 4 minutes. Mix steak and vegetables together. Remove from heat.
06 - Remove mushrooms from oven. Drain any accumulated liquid from the caps.
07 - Fill each mushroom cap with steak and pepper mixture. Top evenly with shredded cheese.
08 - Return to oven and bake for 8 to 10 minutes, until cheese is melted and bubbly.
09 - Serve hot, garnished with fresh parsley if desired.

# Expert Advice:

01 -
  • It tastes indulgent and completely satisfying without the bread guilt that usually follows.
  • The portobello caps get creamy and tender from the oven, creating a perfect edible container that actually absorbs all those savory juices.
  • You can have dinner on the table in 40 minutes, which means weeknight cooking doesn't have to feel like a production.
02 -
  • Drain that liquid from the roasted mushrooms or your filling will turn soggy—I learned this the hard way by not draining and ending up with a waterlogged first attempt that taught me the importance of this one small step.
  • Don't skip the initial 10-minute mushroom roast; it's what transforms them from raw and rubbery to tender and receptive to the filling.
03 -
  • Ask your butcher to slice the steak thin for you—it only takes them a moment and it saves you time and frustration at home.
  • The secret to melty, creamy cheese is using a mix of both provolone and mozzarella if you have them, since provolone brings flavor and mozzarella brings the melt.
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