Peel the asparagus and cut off the woody ends. Wash the asparagus and cook in boiling salted water for 15 minutes, then drain. Heat 1/8 litre of water. Stir in the contents of the bag with a whisk and bring to the boil.
Cut 125 g butter into pieces and gradually beat into them over a low heat. Remove the asparagus, let it cool down a bit and cut it in half. Spread the breads with the remaining butter. Cover with asparagus and ham.
Halve the peaches, cut them into a fan shape and place them on the asparagus. Spread the sauce over them. Place the asparagus breads on a baking tray and bake in a preheated oven (electric range: 225 ° C/ gas: level 4) until golden brown.
Arrange the breads on a plate. Garnish with tomato, lemon and chervil.