Preheat the oven to 400 degrees.
Lightly grease a standard muffin tin with oil or cooking spray.
In a mixing bowl, whisk together the eggs and sour cream until smooth.
Remove the mushroom stems and tear each mushroom into roughly three pieces instead of slicing them.
Add the raw pork sausage, torn mushrooms, salt, and black pepper to the egg mixture and stir until evenly combined.
Fill each muffin cup about three quarters full.
Bake for 20 minutes or until the egg cups are puffed and the centers are fully set.
Allow the egg cups to cool for several minutes before carefully removing them from the muffin tin.
