Place the flour on the work surface so as to form a fountain, add salt and oil and start kneading, gradually adding lukewarm water until the dough is compact and well strung together. Form a ball, wrap it in cling film and leave it to rest for 30 minutes.
Clean the chicory, blanch it for a few minutes in boiling salted water and chop it roughly. Slice the onions and sauté them in a pan with 3 tablespoons of oil. Add the capers, olives and chicory and continue cooking until all the water has evaporated. Set aside to cool.
Roll out the dough into two round, thin sheets. Line the bottom of a 24-cm pie tin with the first sheet. Add the filling and the diced mild Provolone Valpadana P.D.O.. Cover with the second sheet and seal the edges. Bake at 200° C for about 30 minutes, until golden brown.
Remove from the oven and allow to cool. Serve.