Cut the base of the endives and separate the leaves, trying to leave 3 or 4 in each bunch.
Put in a baking tray, pour some olive oil and 2 tablespoons of sugar over them. Put in the preheated oven at 400°F for 5 to 10 minutes or until they start to brown.
For the gratin:
Put the grated cheese in a bowl along with serrano ham, thinly diced, then cream and ricotta. Stir, season with salt and pepper, and lastly add rough bindweed fruit (you can leave some to put on top).
Spread the mixture over the browned endives and grate at 430°F for 15 minutes.