In Donal's own words, 'I’m a self taught home cook who writes and photographs food for a living. I’ve been cooking from an early age ...
1 tblsp butter
Squeeze of lemon juice
1 large cooked potato
Salt and pepper
Mash the potato very well and separate the yolks from the whites of the eggs. Add the yolks to the potato, mixing very well, then season to taste and add the lemon juice.
Heat the pan with butter. Whisk the whites stiffly, stir into the mixture, and then add to the heated pan.
Cook the bottom until golden, then put under a hot grill to finish the top. Originally the top was finished with a 'brander' which was a heated disc of metal, often used in conjunction with the girdle or griddle, for baking.
Variations: I often add a tablespoon of chopped herbs or a very small amount of grated cheese to the above mixture.
In Scandinavia an omelette is invariably baked in a greased dish in the oven (as for a puffy omelette) and 4 eggs would have about a 150ml (¼ pint) cream beaten into them.
In Portugal an omelette is a very odd 'bird', consisting of beaten eggs usually combined with cooked brains, or chopped cooked meats, all mixed together so that the eggs coat the meat. It is quite dry, served in a small heap, but not unpleasant to taste. It is, however, rather a shock if you are expecting a golden, bubbling plateful of food like a tortilla or a French omelette, for it resembles an overcooked piperade and defies all the things I have written about above.