Preheat oven to 375 F. Lightly grease a 24-cup mini muffin tin and set aside.
In a large bowl, combine flour, baking powder, salt, oregano, and parsley. Set aside.
Heat olive oil in a skillet over medium heat. Add mushrooms and a pinch of salt and saute until mushrooms begin to release liquid, 2-3 minutes. Add spinach and garlic and saute for another 2 minutes, until spinach is wilted and garlic is fragrant. Remove from heat.
Add egg, milk and cheese to the flour mixture and stir gently just to combine. Stir in mushroom/spinach mixture. Let stand for 10 minutes.
Gently stir the batter. Divide evenly between the cups of the muffin tin. Bake for 20-22 minutes, until set and browned on top.
Serve warm with warm marinara.
Notes
If not using immediately, freeze the bites in the muffin tin. When frozen, transfer to a freezer safe container. Reheat at 350 for 8-10 minutes.
Recipe by Baked In at https://www.baked-in.com/2014/01/31/spinach-mushroom-pizza-bites/