In a medium bowl, mix together the ricotta and egg. Mix in the fontina, 1/2 cup parmesan, 1/2 tsp. salt and 1/4 tsp. pepper.
Using the pasta dough and cheese filling, make the tortelloni.
In a large pot of boiling, salted water, cook the tortelloni, stirring, until al dente, about 5 minutes.
Meanwhile, in a large, heavy skillet over medium heat, melt the butter. Add the garlic and cook for 2 minutes. Stir in the cream and simmer. Using a spider or small strainer, transfer the pasta from the pot of water to the skillet. Stir in the tomatoes and 1/2 cup of the pasta cooking water. Sprinkle with 1/2 cup parmesan and simmer. Serve with more parmesan.