• 6 ounces thin sliced sirloin steaks
  • 1/8 teaspoon kosher salt
  • black pepper to taste
  • cooking spray
  • 3/4 cup diced onion
  • 3/4 cup diced green pepper
  • 1/4 cup light sour cream
  • 2 tablespoons light mayonnaise
  • 2 oz light cream cheese, softened
  • 3 oz shredded mild provolone cheese, or cheese of your choice
  • 4 medium portobello mushrooms, with no cracks
  1. Preheat the oven to 400F. Spray a baking sheet with oil.
  2. Gently remove the stems, scoop out the gills and spray the tops of the mushrooms with oil, season with 1/8 tsp salt and fresh pepper.
  3. Season steak with salt and pepper on both sides.
  4. Spray a large skillet with cooking spray and heat on high, let the pan get very hot then add the steak and cook on high heat about 1 to 1 1/2 minutes on each side, until cooked through.
  5. Transfer to a cutting board and slice thin, set aside.
  6. Reduce the heat to medium-low, spray with more oil and saute onions and peppers 5 to 6 minutes, until soft.
  7. Combine all the ingredients in a medium bowl. Transfer to the mushroom caps, about 1/2 cup each.
  8. Bake in the oven until the cheese is melted and the mushrooms are tender, about 20 minutes.


  • Meal Type: Dinner
  • Serves: 1
  • Total Time: 30 min
  • Calories: 256
  • Net Carbs: 6g

What is a Philly Cheesesteak Stuffed Portobello? 

The Traditional Philly Cheesesteak is a sandwich that contains a combination of thinly sliced beef, lots of melted cheese, and sliced bell peppers. This hearty sandwich originates from Philadelphia and was invented by a man named Pat Oliveri who decided to replace hot dogs with sliced beef. To make this traditional sandwich keto-friendly, the bun on a traditional Philly Cheesesteak is replaced with large portobello mushrooms, hence the name “ Philly Cheesesteak Stuffed Portobello Sandwich.”

Why Mushrooms?

Edible mushrooms provide differing amounts of fiber and protein. They also contain B vitamins and a potent antioxidant called selenium that helps strengthen the immune system and avoid cell and tissue damage.

In fact, some mushroom types have been found to have the ability to defend against cancer by shielding our cells from DNA damage but also by inhibiting the development of tumors. There is also considerable proof that in the diagnosis and control of neurodegenerative disorders such as Alzheimer's, they may be helpful.

But Portobello Mushrooms?

An average cheesesteak contains 900 calories, 40 g of fat, 50 g of protein, and 80 g of carbohydrates which is fine for an occasional indulgence, but not something you would want to eat every day. But, since steak and mushrooms work so well together, so why not make a meal with this cheesy deliciousness and have a yummy steak with just 256 calories and 6g net carbohydrates.

Let's Get Cooking!

The Philly Cheesesteak Stuffed Portobello can be prepared quickly in about 30 minutes.

To start, gathering your raw ingredients and cut them accordingly. For the portobello, gentle remove the stems and scoop out the gills completely. 

Next, start cooking your raw ingredients to your liking. For us, we enjoy our streak medium rare. 

The last step is to combine your ingredients altogether, transfer the mixture into the mushroom caps and bake them in an oven until the cheese is melted.

Can Philly Cheesesteak Stuffed Portobello be stored?

Yes! You can prepare your Philly Cheesesteak Stuffed Portobello earlier than you need it, or even prepare in excess. All you need to do is store them in the fridge then, whenever you are ready to eat, remove them and bake, grill, or microwave.

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