First prepare the dough. Mix flour, salt and butter. Add water and knead into a dough. Put the dough in the refrigerator for about 2 hours.
For the topping, cook the asparagus tips (about 2 cm long) until not quite soft. Add to the cooking water, salt, a pinch of sugar and a small piece of butter. Strain and drain.
In a frying pan, fry the finely chopped bacon (add a little oil if necessary) and the finely chopped onion. Then add the finely chopped ham and fry briefly.
Add the asparagus tips and season with salt. Preheat the oven to 250 °C. Roll out the dough and place it in the greased quiche dish. Cut away the overhanging edges and use the cuttings to reinforce the edge and/or decorate the quiche.
Prick the bottom of the dough several times with a fork. Sprinkle with cornmeal (absorbs the excess liquid) and spread the asparagus on top.
For the glaze, beat the eggs and season with salt, pepper and nutmeg. Mix in the sour cream and Parmesan and spread evenly over the asparagus mixture.
Bake the asparagus quiche in the oven on the lowest setting for about 30 minutes.