PASTA: Bring 4-6 quarts of water to a boil, and add salt to taste. Add pasta to boiling water and cook until al dente about 11 minutes, stirring occasionally. Meanwhile prepare Alfredo.
ALFREDO SAUCE: Melt butter in a medium, non-stick saucepan over medium heat.
Add cream cheese and garlic, stirring with wire whisk until smooth. Slowly add milk whisking to smooth out lumps. Stir in 1/2 cup Parmesan and season with black pepper.
Remove from heat when sauce reaches desired consistency. Sauce will thicken rapidly, thin with more milk if needed; set aside.
Drain the pasta and immediately rinse under cold water. Pour the pasta back into the pot. Add olive oil, 1/2 cup Parmesan cheese and 1/2 cup Mozzarella cheese. Gently stir the pasta until evenly coated.
Grease a 9-inch springform pan with butter. Tip the pan at a 45-degree-angle and start placing the Rigatoni pasta into the pan so it's standing up. Pack the pasta in the pan tightly for best results.
Pour Alfredo sauce over the pasta allowing it to fill the holes. Sprinkle remaining Mozzarella cheese evenly over the pie.
Bake at 400 degrees for 20 minutes or until the cheese is melted and golden brown.
Remove pie from the oven to a wire rack; cool for 5 minutes. Garnish with fresh chopped basil.
Carefully run a knife around the edges, and unclamp the outer part of the pan, which should slide right off. Cut into wedges and serve with a crispy green salad and French bread.