Brunch Vegetable Frittata Recipe

In a large nonstick skillet, melt butter and cook onions til tender. Add potatoes, broccoli, and zucchini, cover and cook til tender. Stir occasionally. Add spinach and stir in. Beat eggs in a medium bowl til frothy and pour over vegetables in skillet. Sprinkle with cheese over all and lower heat to medium low. When sides begin to set, put skillet in oven under broiler. Watch carefully until top is set and golden brown. Should be no "runny movement" when the skillet is lightly shaken. Slice in pie wedges. Serves 8-10,