Tomato Mushroom Breakfast Muffins bake up into one of the best breakfast meals ever! These amazing vegetarian breakfast muffins have grape tomatoes, mushrooms and bell peppers in an eggy, cheesy custard. They’re baked in hash brown potato nests for taste and stability. Perfect for a holiday breakfast. These Breakfast Muffins can easily be frozen and reheated for later use. Healthy, gluten free, vegetarian.