Boil the potatoes. When cooked, let them cool and then slice them.
Wash, dry and cut the radicchio.
Pour the olive oil into a non-stick pan and fry the shallots, being careful not to burn them. After three minutes add the pine nuts and then the radicchio and allow to cook for about 10 minutes. Add some salt.
Grease an ovenproof pan and alternate layers of potatoes, Taleggio and Parmesan (or vegan alternatives) and radicchio. Complete with a lawyer of potatoes and sprinkle a generous quantity of breadcrumbs, chopped parsley, Parmesan or nutritional yeast flakes, and some butter or margarine on top.
Put the casserole in the oven for about 20 minutes at 160°C/325°F/gas mark 3. This dish can be served hot or cold.