Cook the pasta in salted water until al dente. Reserve 1 cup of pasta water, then drain.
Melt 2 tablespoons of the butter in a large skillet over medium-low heat. Add the garlic and cook for about 30 seconds.
Add the crushed tomatoes and simmer for 10 to 12 minutes, stirring occasionally.
Add the drained pasta, remaining butter, and Parmesan. Toss well, adding reserved pasta water a little at a time until the sauce is glossy and coats the pasta.
Taste and add black pepper or a small amount of salt if needed. Serve immediately.