I like fritatta, a crustless quiche.
I typically par cook or cook vegetables before assembling the fritatta. They are super forgiving.
You can do a themed fritatta, like a mexican one, with veges, peppers, onions and garlic, plus cheese of course. You can even sprinkle corn chips over the top. Or italian. One of my favorites was a french onion soup themed one with caramelized onions and gruyere cheese.
To make a general vege fritatta I will cook onions til translucent and allow to cool, then par cook any hard veges like diced carrots or broccoli cut into small in salted boiling water. Basically the veges need to be cooked til ALMOST done because the eggs cook so fast. I let everything cool down, then mix it all in a big bowl with uncooked chiffonaded greens like spinach or chard (if I use kale I “massage” the chiffonade to tenderize it a little). It will look almost like a salad with A LOT of dressing, heat butter in a skillet, add the egg / vege mixture and once the bottom has set, pop into the oven and continue to cook til the top sets. At some point I typically add cheese as well. But that’s if I’m doing a “stained glass” frittata I will serve in gorgeous thin slices.
For a basic fritatta, in a cast iron pan melt butter and cook some onions til translucent, add more veges and cook til almost done, pour over cooked veges, let the bottom set, top with some cheese and pop into a medium oven til the eggs are just set. It’s super easy and makes a great breakfast, lunch or dinner.
Depending on the size of my pan I typically use 9-11 eggs in a fritatta.