This is a very simple omelette, ideal for when you need something tasty on the go! Adjust the garlic to taste, especially if you are on your way to work...and feel free to add a splash of something spicy, if it's that kind of day.
In a non-stick frying pan over a high heat, melt the butter then add the garlic. Cook and stir for several minutes until quite crispy and golden brown. Lower the heat to medium then add the courgette and mushrooms; cook and stir for several minutes until golden brown.
Increase the heat to medium high, spread the courgettes and mushrooms out over the base of the pan then pour in the eggs. Pick up and tilt the pan if necessary to spread the egg around. Working quickly, sprinkle the cheese over and season with salt and pepper, lower heat to medium. When you start to see the top of the omelette bubbling give the pan a wiggle to loosen the base.
I like my eggs cooked very well, so I flip my omelette over in the pan and cook until dry before folding and transferring to a warm plate. However, when the cheese has melted on top and the egg is to desired consistency you can either fold over and serve at this stage if you like them a bit runny, or place under the grill for a moment or two to finish. Whatever your preference, this is a forgiving omelette and should stay together well.