Preheat oven to 400 degrees. Heat 1 tablespoon of the olive oil over medium-high heat in a nonstick 10 inch oven proof skillet and add the mushrooms. Cook, stirring often, until they begin to wilt about 3 to 5 minutes. Add salt, pepper and the garlic powder. Add the spinach and stir until wilted. Turn up the heat and let any excess liquid evaporate from the pan, then remove from heat.

Beat the eggs in a large bowl, add water and the mushroom spinach mixture. Mix in the goat cheese.

Heat the remaining olive oil over medium-high heat in the skillet. Pour the egg mixture into the pan and cook, scraping the sides with a rubber spatula. Once the eggs have started to cook, turn the heat down to low and cook for about five minutes or until eggs are starting to set.

Transfer skillet to oven for 8 to 10 minutes, until frittata is golden and puffy

Loosen the edges with a spatula. Carefully slide from the pan onto a large round platter. Cut into wedges. Serve hot, warm, room temperature, or cold. Season with more salt and pepper to taste if desired.