Cook pasta in a large pot of salted water for 8-9 minutes, al dente (do not overcook). In a large skillet or pot add 1 T. of oil on medium heat. Sauté onions for 1 minute then add the beef and brown and crumble. Add the sauce mixture, stir, and let simmer on low for 15 minutes, uncovered, stirring occasionally. Preheat oven to 350 degrees. Mix sauce and pasta. Layer ½ the pasta into a 9x13 dish. Sprinkle half the cheese on the layer, lay out the provolone slices, spread all the sour cream on the layer. Top with remaining pasta, and mozzarella. Bake uncovered for 30 minutes. Broil for 30 seconds at the end to brown cheese. Serve.
