Keto Philly Cheesesteak Mushrooms (Printable version)

Savory stuffed portobello mushrooms with tender steak, peppers, and melted cheese in a low-carb style.

# What You Need:

→ 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

# How to Make It:

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 4-5 minutes until softened.
04 - Add minced garlic and cook for 1 minute. Push vegetables to the side of the skillet.
05 - Add sliced steak to skillet, season with salt, pepper, and smoked paprika. Cook while stirring until just browned, approximately 3-4 minutes. Combine steak and vegetables together. Remove from heat.
06 - Remove mushrooms from oven and drain any accumulated liquid from the caps.
07 - Fill each mushroom cap with the steak and pepper mixture. Top evenly with shredded cheese.
08 - Return to oven and bake for an additional 8-10 minutes, until cheese is melted and bubbly.
09 - Serve hot, garnished with fresh parsley if desired.

# Expert Advice:

01 -
  • It tastes indulgent and restaurant-worthy while keeping you solidly in keto territory.
  • The portobello caps release their own moisture during cooking, creating a natural sauce that soaks into the filling.
  • Everything comes together in about 40 minutes, no special equipment needed.
02 -
  • Removing the mushroom gills before cooking prevents the dish from becoming watery—this was the difference between something soggy and something perfect.
  • Don't overcrowd the skillet when cooking the steak or it will steam instead of brown, so work in batches if needed.
03 -
  • Buy your steak fresh and ask the butcher to slice it thin, or partially freeze it for 20 minutes at home and slice it yourself—pre-sliced packages are often thicker than ideal.
  • If your mushroom caps have thick, dense gills, scrape them out gently with a spoon before cooking, which speeds up cooking and prevents excess moisture from pooling.
Return