Once upon a time, I loved frittatas, which are impressive-looking yet really simple (and pretty foolproof) egg-based casseroles that are often full of cheese. You can make dairy-free frittatas, like this one: http://www.lifeisapalindrome.com/recipes/really-tasty-rutabaga-and-zucc… . But here is a pretty simple formula for making a tasty, cheesy version, which I don't serve very often but really like a lot. :)
--1/4 cup fat of your choice (refined coconut oil, lard, butter, etc.)
--1 medium onion, or 1 large shallot, minced
--1 or 2 scallions, chopped
--Several cloves of garlic, minced, optional
--1 bunch broccoli, or kale, or greens of your choice, chopped or separated into florets
--ground black and/or red pepper to taste
--3/8-1/2 tsp. salt (use the larger amount of you like things salty)
--herbs and spices if you want (~2 tsp. basil and ~.5 tsp. oregano is nice)
--12-15 eggs (use the smaller amount if you are also using yogurt)
--up to 1 cup yogurt, optional (makes the frittata more tender, the more you use)
--1/4 cup melted butter
--a few tbsp. chopped parsley, optional
--3/8-1/2 tsp. salt
--8 oz. grated cheese
--Thinly sliced veggies to decorate the top (tomato, red peppers, etc.)
Butter a 9x13 casserole, or the equivalent, and preheat the oven to 350f. Enamel-lined pans are easier to clean.
Saute the onion or shallot until it just starts to brown. Add garlic and scallion, and stir for 30 seconds or so; add broccoli/greens/veggies, and cook until partway done (they will cook more in the oven), about five minutes. Stir frequently. Season with spices and salt and pepper until tasty, or just salt and pepper if you want the vegetables' flavor to shine through.
Beat eggs with yogurt (if using), melted butter, and chopped parsley (if using).
Spread vegetable mixture evenly in the prepared pan. Sprinkle the cheese evenly over this. Pour egg mixture evenly over the top, and place thinly sliced veggies decoratively over the top of this.
Bake for 30-45 minutes, until the center is barely firm, the frittata is puffed and golden but not too brown, and the inside temp. registers 160 on an instant-read thermometer.