Over a low heat, soften the onions with a small amount of olive oil in a small (22cm) non-stick pan. Add the chervil, seasoning and then a third of the beaten eggs and increase the heat. When the omelette is cooked to your taste, place it on a plate and repeat the procedure to make three omelettes.
Place one omelette flat on a plate and cover it with three slices of Comté. Cover this omelette and the cheese with another omelette, more slices of Comté and finish by placing another omelette on top. Cut the cake into 2x2cm squares and place cocktail stick through the centre.