To prepare the quiche with asparagus and mortadella, start with the shortcrust pastry.

1. Put the sifted flour together with the cold butter into small pieces in a mixer equipped with blades; add a pinch of salt and blend everything until you get a mixture with a sandy and floury appearance.
2. At this point, flavour the dough with some thyme leaves and knead everything quickly, adding the cold water a little at a time.
3. When the dough is compact and elastic, wrap it in cling film and rest in the refrigerator for at least 40 minutes.

In the meantime, dedicate yourself to the filling:

1. clean the asparagus, wash them under fresh running water, peel them with a potato peeler, and then tie them with kitchen string.
2. Place a saucepan on the fire and cook them in cold salted water for about 15 minutes, covering with a lid, then drain and let them cool.
3. Divide 3-4 asparagus in half lengthwise; they will be used for decoration. Cut the rest into thin washers, keeping aside the tips to use for the final decoration.
4. Finely chop the shallot and let it dry slowly in a non-stick pan with the oil.
5. Cook the asparagus in rounds with the shallot, letting it flavour for 3-4 minutes. Meanwhile, cut the mortadella into cubes and sprinkle the thyme.
6. In a bowl, mix the ricotta and milk with the help of a whisk, then add the previously beaten eggs and the grated cheese.
7. Add the diced mortadella and the cold asparagus to the filling; mix with a spatula until the mixture is smooth and season with salt and pepper.
8. After the necessary time, roll out the dough with a rolling pin on a lightly floured pastry board.
9. Grease a ceramic pan with a diameter of 24 cm and lay the pastry on it; gently adhere the base and edges with your fingers, then cut out the excess edges with a small knife.
10. Pour the filling, level it well with a spatula and decorate the surface with the remaining asparagus cut in half lengthwise, creating a diamond pattern. Complete the decoration by inserting the asparagus tips that you have kept aside, distributing them as desired.
11. Fold the edge of the quiche inwards, brush the asparagus with a bit of oil and bake in a preheated static oven at 160 ° for about 85 minutes (or at 140 ° for 75 minutes).
12. Once ready, take it out of the oven and let it cool before serving it.