Source: One United Harvest Cookbook

Serves 20 as an appetizer or 8 as an entree, great for potlucks!

2 T butter or olive oil
1 small yellow onion, chopped
2 garlic cloves, finely chopped
6-8 oz spinach
1 dozen eggs
1/2 lb feta cheese
1/4 lb grated jack cheese
1/2 t salt
1/4 t pepper

Heat the butter or oil in a medium saucepan over medium heat. Add the onion and garlic and cook until soft. Remove from pan. Add spinach to the same pan and cook until wilted. Set aside to cool. Squeeze excess liquid out of the spinach and chop coarsely. Break the eggs into a large bowl and whisk until blended. Add remaining ingredients. Pour into a 3 quart baking dish or a 9 by 13 inch baking pan. Bake at 350 degrees for about 30 minutes or until frittata is set. Serve warm, cold or at room temperature. Tomato salsa goes really well with this dish!