I cut a large butternut squash into quarters lengthways. Season. Spray with a little Fry Light. Roast in the oven for at least an hour, until the flesh is soft. When cooled, scoop the flesh out of the skin.
Chop a large red onion. Soften in a large frying pan, using a little Fry Light and a splash of water. Add the squash flesh.
Leave the pan on the heat at about medium.
Beat 10 eggs in a bowl. Crumble a pack of low fat feta/salad cheese through the eggs. Season with salt and pepper. Add a tsp or so dried Rosemary.
Pour the mixture into the pan, over the onion and squash. Mix a little.
Preheat your grill to medium.
Cook on the hob until the sides of the omelette look like they are setting. Take the pan off the heat and put under the grill (please make sure your pan has a metal handle, or you can remove the handle before putting it in the oven!!).
Grill until the top of the omelette is set.
Remove from all heat. Using a fish slice, spatula, or similar, encourage the sides and bottom of the omelette away from the pan (it will probably have stuck a little in the middle).
To remove the omelette from the pan: put a large plate or serving dish over the pan; holding the plate and pan together (use a tea towel to protect hands from hot pan), carefully flip the pan upside down so the omelette leaves the pan for the plate (beware omelette dribbles!).
Serve with salad.
I wrapped mine in tinfoil and a towel and took it on a picnic. It was still a little warm when we ate it with a roast vege salad, with views over Dollar Glen, Clackmannanshire, the Forth, and beyond.