Cook garlic and oil in 12-inch stainless-steel skillet over medium heat until fragrant but not brown, about 2 minutes.
Add sausage and cook, breaking up meat with wooden spoon, until no longer pink, 3 to 5 minutes.
Stir in tomatoes, salt, and sugar. Bring to gentle simmer and cook, stirring occasionally, for 10 minutes.
Stir in water and penne, increase heat to medium-high, and bring to vigorous simmer.
Reduce heat to medium, cover, and cook, stirring occasionally, until pasta is nearly al dente, about 8 minutes.
Uncover and continue to cook, stirring gently, until pasta is al dente and sauce is thickened, 4 to 7 minutes; if sauce becomes too thick, add extra water as needed.
Off heat, stir in basil and season with salt and pepper to taste.
Serve, passing Parmesan, if using, separately.
