Freezing Egg & Cheese Omelet
Quite surprising, but cooked eggs (hard boiled, scrambled and omelets) freeze particularly well. I keep large thin omelets for shredding over fried rice. Cheese and egg are mostly composed of fats and proteins that freeze well. I would think that most omelets composed of cheese would work well. I can also see a spinach omelet made with frozen spinach working well as well.

I would avoid trying to freeze an omelet that contained crispy/crunchy vegetables. Or maybe omelets with a saucy filling that may split during reheating.