Warm a non-stick pan on low heat. Put one crêpe on it. When it is warm enough put a little piece of butter and spread all over the crêpe the melted butter. Then turn over the crêpe.
Crack an egg in the middle of the crêpe. With a spatula try to spread evenly the white egg and keep the yolk in the middle of the crêpe. When it starts to cook put the ham around then the cheese. Fold the edges around it but try to not cover the egg yolk. When the yolk seems cooked. Serve immediately.