Boil 2 (3-ounce) packs of ramen (save the seasoning packets for another use), reserving ½ cup of the cooking water.
Whisk together ¼ cup peanut butter, 2 tablespoons chili garlic sauce, 2 tablespoons soy sauce, and the reserved hot water until smooth.
Drain the noodles, toss with the sauce until coated, and garnish with thinly sliced scallions and toasted sesame seeds if using.
