Pasta alla Marlboro Man

2 tablespoons olive oil
2 pounds ground beef
1/2 large onion, diced
2 cloves garlic, minced
Salt to taste
Freshly ground black pepper to taste
1 generous teaspoon ground thyme
3 14-ounce cans whole tomatoes
1/4 cup freshly grated Parmesan cheese, plus more for sprinkling
1 1/2 to 2 pounds rigatoni

Heat olive oil in large skillet or pot over medium-low heat. Add onion and cook a couple of minutes, until starting to turn translucent. Add garlic and stir, cooking 1 minute, making sure not to brown the garlic.
Add ground beef and cook until brown. Drain most of excess fat.
Add salt, pepper, and ground thyme. Stir to combine.
Dump in canned tomatoes with their juice. Stir, reduce heat to low, and cover pot. Cook for 30 minutes, stirring a couple of times.
Uncover the pot and cook an additional 30 minutes.
Cook rigatoni according to package directions—don’t overcook! Drain and place individual portions into bowls.Stir in 1/4 to 1/2 cup grated Parmesan into the sauce. Check and adjust seasonings. Ladle sauce over cooked pasta, sprinkle with more Parmesan, and serve.

http://thepioneerwoman.com/cooking/2009/03/monday-night-dinner-pasta-alla-marlboro-man/