Start by making the Arrabiata tomato sauceand let it simmer away on gentle flame while working on the meatballs.
Soak the sliced bread in the milk for a few minutes, squeeze the milk out and add the bread to a bowl. Combine it with the ground beef, garlic, parsley, baking soda,ricotta cheese, salt, pepper and the egg.
Mix everything with wet hands and add the bread crumbs. Shape the mixture into golf ball size meatballs and arrange them on a cookie sheet.
Press 1 cube of the fontina cheese into each meatball and reshape to encapsulate the cheese completely. Transfer each meatball into the simmering sauce making sure to coat evenly. Cover with a lid and let them simmer in the sauce for about 5 minutes or until cooked through.
Meanwhile cook the spaghetti according to the instructions on the package and toss them with the marinara or arrabiata sauce. (Reserve the rest of the sauce for later ) Transfer to a serving platter and add the meatballs on top. Grate some parmigiano reggiano on top and sprinkle with some parsley and basil leaves.
Make the tomato sauce first and half way through, start working on the meatballs, and cooking your pasta.