Preheat your oven to 375°F (190°C).

Season the sirloin steak with salt and black pepper. Heat olive oil in a large skillet over medium-high heat, add steak, and sear for 2-3 minutes. Transfer to a plate to rest.

In the same skillet, melt butter, add minced garlic, and sauté for 30 seconds. Stir in flour, cook for 1 minute, then whisk in milk and beef broth until smooth. Continue stirring until thickened.

Remove from heat and stir in cheddar cheese, Dijon mustard, and paprika until melted and creamy.

Cook tortellini according to package instructions. If using fresh, cook slightly under. Drain and drizzle with a bit of olive oil, then mix gently with seared steak.

In a greased baking dish, combine tortellini, steak, and cheese sauce, mixing evenly. Top with shredded mozzarella cheese.

Bake uncovered in the oven for 20-25 minutes until cheese is melted and bubbly.

Let casserole rest for a few minutes, then garnish with chopped parsley before serving.