Slice garlic thinly and cook it gently in butter and olive oil over medium heat for 2-3 minutes until fragrant but not browned; browning creates bitterness that ruins the delicate truffle flavor.

Add heavy cream slowly to the infused butter and bring to a gentle simmer, never a rolling boil, which can cause the cream to break and separate into greasy pools.

Save at least one cup of starchy pasta water before draining, then add it gradually (2-3 tablespoons at a time) to achieve the perfect silky consistency without making the sauce too thin.

Remove the sauce from heat before stirring in mozzarella and Parmesan; residual heat will melt them smoothly, while direct heat can cause cheese to become grainy and clumpy.

Add truffle oil in the last 30 seconds of cooking or even after plating, as heat diminishes its delicate aromatic compounds; a light drizzle on top also creates a luxurious visual presentation.