Sauté the Veggies: In a skillet over medium heat, heat olive oil. Add onions, bell peppers, and mushrooms. Cook 5–7 minutes until softened. Season with salt, pepper, and garlic powder. Remove from pan and set aside.

Cook the Beef: In the same pan, quickly sear the beef slices for about 1–2 minutes per side, just until browned. Don’t overcook—they’ll finish in the oven. Set aside on a plate.

Assemble Roll Ups: Lay out beef slices. On each, place a slice of provolone cheese and a spoonful of sautéed veggies. Roll tightly and secure with toothpicks if needed.

Bake: Preheat oven to 375°F (190°C). Arrange roll ups in a baking dish or on a parchment-lined sheet. Bake for 10–12 minutes, or until cheese is melted and bubbly.

Serve: Remove toothpicks, garnish with parsley, and serve hot. Perfect with a side of cauliflower mash or a green salad.