Heat 2 tablespoons of olive oil in a large skillet over medium heat for 1-2 minutes.

Add 1 cup of thinly sliced beef, seasoning with salt and pepper. Cook for 4-5 minutes until browned.

Stir in 0.5 cup of diced onions, 0.25 cup of diced bell peppers, and 0.5 cup of diced mushrooms. Sauté for an additional 4-5 minutes.

Remove beef and vegetables from the skillet, set aside to cool slightly.

Place one tortilla in the skillet, layer with a slice of provolone cheese, and follow with the beef and vegetable mixture.

Top with another slice of provolone and cover with a second tortilla. Press down gently.

Cook the quesadilla for 3-4 minutes until golden brown, then flip to cook the other side for another 3-4 minutes.

Repeat the assembly and cooking process with remaining tortillas and filling.

Slice the cooked quesadillas into wedges and serve hot with your favorite dipping sauce.