Created in 1967 by Paul Haeberlin when the restaurant earned its third Michelin star.
2kg frogs' legs
200g pike fillet, deboned
1 clove garlic
2 egg whites
1tbs cooked roux (flour and butter)
1/2 litre whipping cream
150g unsalted butter
Salt and pepper
1/2 bottle dry Riesling
4 shallots, diced
Method To cook the frogs' legs, sweat the shallots in butter until soft. Add half the frogs' legs. Pour over the Riesling. Season and simmer for 10 minutes. Pass the liquid through a chinois into a fresh pan and reduce by half. Strain the frogs' legs, bone them and reserve.
To make the mousseline, bone the meat from the rest of the frogs' legs. Mince them, then blend them in a Robot Coupe with the pike together with the egg whites. Incorporate an equal weight of cream a little at a time. Season.
Meanwhile, cook the spinach in boiling salted water, drain and extract excess moisture, pressing it with your hands. Heat 50g butter in a pan with the garlic clove in its skin. When the butter foams, add the spinach, season and cook out for five minutes.
To finish, butter eight ramekins. Pipe mousseline over the base and around the sides. Fill the cavity with boned frogs' legs. Seal with a layer of mousseline. Bake in a bain marie in the oven for 15 minutes and turn out.
For the sauce, bind the reduced liquid with the roux. Boil, add the rest of the cream and whisk in the rest of the butter. Finish with a little lemon juice and check the seasoning.
Serve the mousselines on a bed of spinach, coated with sauce and garnished with chopped chives.