Heat a large pot over medium heat and add the olive oil.
Add the minced garlic and sauté, stirring constantly, until fragrant and just starting to color, about 1 minute.
Pour in the pasta and then add the milk so the pasta is covered by about 1/2 inch of liquid. Bring to a gentle simmer.
Cooking
Reduce heat to low. Cook, stirring every 1-2 minutes, until the pasta is tender and the sauce is creamy, about 10-12 minutes.
Remove from heat and stir in the grated Parmesan until melted and smooth. Taste and season with salt and pepper.
Serve immediately, garnished with chopped parsley if desired.
Notes
For a richer finish, swap half the milk for half-and-half. For dairy-free, use unsweetened oat or soy milk and a vegan Parmesan option. Cool leftovers and refrigerate for up to 3-4 days. To reheat, add a splash of milk and warm gently.