Add freshly grated Parmesan or Pecorino Romano
Stir in minced garlic sautéed in butter
Use heavy cream or half-and-half for a richer texture
Add a little reserved pasta water to improve consistency
Season with black pepper and a pinch of salt
Add a small amount of cream cheese for extra silkiness
Finish with a pat of butter for a smoother sauce
Add nutmeg very lightly for depth
Mix in cooked chicken, shrimp, or mushrooms for more flavor
Add chopped parsley or basil at the end
Use roasted garlic instead of raw garlic
Add a squeeze of lemon juice for brightness
Simmer the sauce gently with the pasta for better coating
Add red pepper flakes for a little heat
Stir in sautéed onions or shallots for more savory flavor