Bring a large pot of salted water to a boil and cook the pasta until just al dente, about 8 minutes. Drain and set aside.
In a large skillet, melt butter over medium heat until it starts to bubble and smell nutty, about 1 minute. Add the minced garlic and cook until fragrant, just about 30 seconds.
Pour in the milk and heavy cream, stirring gently. Bring the mixture to a low simmer, watching for small bubbles around the edges.
Gradually add the grated cheeses, stirring constantly with a whisk until completely melted and the sauce becomes smooth and velvety.
Stir in the cooked pasta, folding it into the cheesy sauce until evenly coated. Add a splash of hot sauce or a pinch of smoked paprika for that soulful kick.
Taste the sauce and season with salt and pepper as needed. Let it sit off the heat for 2-3 minutes to thicken slightly and develop flavor.
Transfer the mixture to a baking dish if baking for a crispy top, or serve directly from the skillet for a more rustic look. Garnish with chopped green onions or chives to add freshness.