Preheat your oven to 375°F (190°C).

Carefully clean the mushrooms with a damp paper towel, remove the stems and chop them.

In a mixing bowl, combine chopped mushroom stems, cream cheese, sausage or bacon, Parmesan, garlic, parsley, salt, and pepper. Mix until creamy.

Fill each mushroom cap generously with the creamy filling, packing it in gently.

Place one pitted olive in the center of each stuffed cap to create the pupils.

Arrange stuffed mushrooms on the greased baking sheet and bake for 20-25 minutes until tender and golden.

Remove from the oven, let cool slightly, and serve warm on a platter, possibly with marinara sauce.