In a medium skillet over medium heat, brown the ground beef, breaking it apart until cooked through. Drain any excess fat.

In a hot, dry skillet, add your sliced mushrooms. Stir frequently until they become shriveled and golden brown, about 5-7 minutes.

Blend the cottage cheese in a food processor until it is smooth.

In a large mixing bowl, combine the drained ground beef, dry-seared mushrooms, blended cottage cheese, and black pepper. Mix until well combined.

Transfer the mixture into a greased baking dish, top with Swiss cheese, and bake in a preheated oven at 375°F for about 15 minutes, or until bubbly and golden.

Let the casserole sit for 5 minutes before serving.

Optional: Garnish with fresh parsley or chives before serving.