Grill the sausage. Grill your Italian sausage links over medium heat, turning often, until they reach 160°F inside. While the sausage cooks, boil the pasta in salted water until al dente. It will keep cooking in the oven, so don’t overdo it..
Slice the sausage. Let the sausage rest for a couple of minutes, then cut it into ½-inch slices.
Combine everything. Drain the pasta and return it to the pot. Stir in the sliced sausage, the spaghetti sauce, and the basil, cut using a chiffonade technique.
Add the cheese. Stir in about half of the shredded mozzarella. Pour the pasta into a baking dish and sprinkle the rest of the cheese over the top. (I once tried fresh mozzarella, and it turned out too clumpy. Shredded mozzarella melts much more evenly.)
Bake at 400 degrees for about 20 minutes, until the cheese is melted and bubbly.