Pasta Fillings
The fillings for stuffed pasta are as varied as the shapes. The classic cheese filling for ravioli is a blend of ricotta, Parmigiano-Reggiano cheese, egg yolk and nutmeg. Meat fillings are usually reserved for smaller stuffed pastas, such as the celebrated tortellini, which traditionally conceal a mixture of prosciutto, mortadella, veal, pork and Parmigiano-Reggiano. As with other Italian dishes, no codified formula exists for fillings; the recipes vary with longtime customs, family tradition and locally produced meats and/or cheeses.
Stuffed pastas must be sealed perfectly to cook properly. First, using a pastry brush or your finger, lightly paint water, milk, beaten egg or egg yolk mixed with a little water on the pasta around the filling. Then cover the filling with the pasta (usually by folding pasta over the top) and press out all the air as you seal the dough firmly around the filling. Trapped air will cause the pasta to inflate in the cooking pot. If the seal is not secure, the pasta can also break open in the pot and lose its filling.
You will usually need to cook stuffed pasta in two batches to avoid reducing the water temperature too much. First, depending on the recipe, bring broth or salted water to a rapid boil, then gently slip in the pasta. Cover the pot until the water returns to a boil, then uncover and cook, gently stirring occasionally to prevent sticking, for 3 to 5 minutes. Do not let the water boil too hard, or the pastas may knock against one another and break.
Most stuffed pastas are done when they float to the surface, but a simple test is a better indication: using a wire skimmer or slotted spoon, transfer a single pasta piece to a cutting board. Cut off a corner with a paring knife. If the pasta looks cooked through and the corner tastes tender, the pasta is done. Use the skimmer or slotted spoon to transfer the remaining pasta to a warmed serving dish.
Some stuffed pastas are eaten in broth. Others are eaten with a simple sauce and sometimes a little grated cheese, with just butter and cheese, or with a light cream sauce and cheese. Never use a heavy sauce with a stuffed pasta, as it can easily overwhelm its natural delicacy.