This is loosely based on a recipe from the South Beach Diet book, but I changed some things, as I usually do. The flavors in this dish are great, with the saltiness of the feta playing off the sweet tomato.
1/2 C. onion, chopped
1 C. summer squash and/or zucchini, chopped
2 t. butter
2 cloves garlic, minced
1 large tomato or 6-7 cherry tomatoes, diced
3 egg whites
1/2 C. and 1/8 C. feta cheese
1 C. beans (I used pinto, but pretty much any bean would work)
Spices to taste (I used Mrs. Dash Table Blend)
Melt butter in a 10-inch, oven-safe skillet. Saute onions and zucchini/squash in the butter until onions are clear (about 5 minutes). Add garlic, tomato and beans and saute together until the entire mixture is heated through (about another 5 minutes).
Meanwhile, beat the eggs and egg whites with the spices. Add 1/2 cup feta to the eggs.
Distribute the veggie mix evenly over the bottom of the pan and pour over the egg mixture so that the egg covers all of the vegetables. Place pan in broiler and cook until the top is mostly set. Sprinkle the 1/8 cup feta on top and continue broiling until the top of the frittata is set and starting to brown.