Boil the noodles: Bring a large pot of salted water to a boil and cook the spaghetti or egg noodles until just tender, about 8 to 9 minutes. Drain well and set aside, tossing with a small drizzle of oil if they sit for more than a few minutes.

Mince the garlic: Finely mince all 10 cloves of garlic so they melt into the butter instead of staying in large pieces. This step affects how evenly the flavor spreads through the sauce.

Melt the butter: Melt the unsalted butter in a large skillet over medium heat until it foams and starts to smell nutty, about 1 to 2 minutes. Keep the heat steady so the butter doesn't brown too fast.

Sauté the garlic: Add the minced garlic to the foaming butter and stir constantly. Cook until the edges turn pale gold and the kitchen smells toasty, about 45 seconds to 1 minute, then pull the pan off the heat briefly if it starts to darken too fast.

Build the sauce: Stir in the fish sauce, soy sauce, oyster sauce, and sugar. Let the mixture bubble gently for about 30 seconds so the sugar dissolves and the flavors blend into a glossy, dark sauce.

Toss in the noodles: Add the drained noodles to the skillet and toss with tongs until every strand is coated in the garlic butter sauce, about 1 to 2 minutes over low heat.

Check the seasoning: Taste a strand of noodle and adjust with a splash more fish sauce or a pinch of sugar if the flavor feels flat or too salty.

Add the parmesan: Sprinkle the grated parmesan over the hot noodles and toss quickly so it melts slightly into the sauce rather than clumping on top.

Finish with herbs: Scatter the chopped scallions and cilantro over the noodles, along with crushed red pepper flakes if you want some heat. Toss once more to distribute the herbs evenly.

Serve warm: Transfer the noodles to a serving platter or individual bowls while they're still glossy and warm, with extra parmesan on the side for anyone who wants more.