Set 30 g of the butter aside and divide the remainder into three equal pieces. Melt one piece in a small frying pan, add the golden shallot and cook gently until softened. Put the golden shallot into a bowl with the eggs, water, chopped parsley, thyme, salt and cayenne pepper. Whisk well and set aside.
Melt the reserved 30 g butter in the same small frying pan and, when foaming, add the chopped tomato and Worcestershire sauce. Reduce the heat to very low and keep warm.
In a small omelette pan, melt another of the small pieces of butter until it begins to sizzle, then quickly pour in half of the egg mixture and stir with a fork, over high heat, until all the butter is absorbed by the egg. Stop stirring and cook for about 30 seconds, or until the egg is almost set, but still very moist on top. Sprinkle half the cheese over the omelette, fold into three, turn out onto a hot plate and keep warm while making another omelette in the same way.
Spoon half the hot tomato butter over each omelette, garnish with the parsley sprigs and serve immediately with crusty bread and a green salad, if desired.
*Cheese Omelette with Anchovy Butter: Add either 2 ﬁnely chopped anchovy ﬁllets or 1/4 teaspoon anchovy essence to the butter in place of the tomato. *Ham and Cheese Omelette: Reduce the amount of cheese and add 30 g of well-flavoured ham, ﬁnely chopped, to the omelette. Serve with hot tomato butter.