Wash and peel the asparagus and cut off the lower woody ends. For the pancake batter, beat the eggs and salt with the whisk of the hand mixer. Add baking powder and 50 g flour and stir in. Stir in milk and mineral water. Let the dough swell for about 15 minutes. Put asparagus in boiling salted water and cook for about 18 minutes.
In the meantime, wash lemon thoroughly and grate finely. Halve the lemon and squeeze the juice. Heat clarified butter in portions in a pan and bake 4 pancakes of the batter one after the other until golden brown. Keep the pancakes warm. Heat the fat in a saucepan. In the meantime, lift the asparagus out of the asparagus water, keep warm and measure 400 ml of asparagus water. Dust the melted fat with the rest of the flour, sweat it on and stir in the measured asparagus water and cream. Add lemon peel. Season sauce with salt, pepper, sugar and lemon juice. Cover each pancake with 2 slices of ham, roll up loosely and divide into three as desired. Arrange asparagus, sauce sprinkled with pepper, crespelle and remaining ham on a plate.
In the meantime, lift the asparagus out of the asparagus water, keep warm and measure 400 ml of asparagus water. Dust the melted fat with the rest of the flour, sweat it on and stir in the measured asparagus water and cream. Add lemon peel. Season sauce with salt, pepper, sugar and lemon juice. Cover each pancake with 2 slices of ham, roll up loosely and divide into three as desired. Arrange asparagus, sauce sprinkled with pepper, crespelle and remaining ham on a plate. Garnish with chervil as desired. Add remaining sauce extra