If you're looking for a vegetarian option, these spinach and feta stuffed mushrooms are a perfect choice. To make this recipe, you'll need fresh mushrooms, spinach, feta cheese, onions, garlic, and breadcrumbs. Start by sautéing the onions and garlic until they are soft and fragrant. Add the spinach and cook until wilted. In a bowl, mix together the cooked spinach mixture, crumbled feta cheese, and breadcrumbs. Stuff each mushroom cap with the filling and place them on a baking sheet. Bake in a preheated oven at 375°F for about 15-20 minutes or until the mushrooms are tender and the filling is heated through. These spinach and feta stuffed mushrooms are packed with flavor and make a great appetizer or side dish.