This is one that I like to make if for just the two of us, but would work well as a double batch for a sunday brunch with company! You can switch up the cheese, and the veggies in this to accommodate your taste.
Heat 1 tbsp olive oil in med to large pan or skillet on med heat. Beat your eggs, salt and pepper in a bowl set aside. Into the pan throw in your mushrooms and onions cook for about 4 minutes till a bit tender. Add Onions and Mushrooms to egg mixture and stir together, put 1 tbsp of olive oil in pan then transfer mixture back to pan cook on one side until there is no more liquid on top or until it is nice golden brown underneath. Flip carefully, spread cheese all over cooked area, lay spinach over the cheese, fold over right away and let the cheese melt, this will soften up the spinach as well. Use your flipper and cut folded omellette in half and serve.