While the butter is melting, chop the mushrooms and add them to the butter; stirring occasionally – cook for about 5 minutes, or until the mushrooms begin to soften and brown slightly
While the mushrooms are cooking, dice the tomatoes and chop the green onions.
Mix all the ingredients, except the Egg Beaters together and then divide the ingredients among all 4 ramekins.
Slowly pour the Egg Beaters into the ramekins and season with salt and pepper
Bake in oven for about 20 minutes, or until the Egg Beaters are cooked to your liking.
Notes
For adults, or those who like a bit of a kick to their frittatas - add 1 tsp of hot sauce to each fritattata and gently mix before cooking