Chef John's Pizza Rustica
If you don't have a pastry blender, you can use your fingertips to blend the butter and flour together.
Make this with whatever combination of cheese you want, like Parmesan, provolone, or Fontina. Use either sweet or spicy Italian sausage, and try other meats like coppa, prosciutto, or gabagool.
You could cook this in other large baking dishes, but a 9-inch springform pan is the best choice.
Double the dough recipe if you want to be sure you have enough to work with.