Step 1

Bring a large saucepan of water to a boil over medium-high heat. Meanwhile, make the sauce.

Step 2

Mince 2 garlic cloves. Peel and mince 1 (1-inch) piece ginger until you have 1 teaspoon. Place both in a large bowl. Thinly slice 2 medium scallions; add the scallion white and light green parts to the bowl and reserve the dark green parts for garnish.

Step 3

Add 1/4 cup peanut butter, 1 tablespoon Chinese sesame paste, 2 tablespoons soy sauce, 2 tablespoons rice vinegar, 2 tablespoons hot water, 1 tablespoon granulated sugar, 1 tablespoon toasted sesame oil, and 1 teaspoon Asian chili-garlic paste to the bowl and whisk until creamy and combined (it will look curdled at first). Cut 1/3 medium English cucumber into matchsticks (about 1 cup) and add to the bowl of sauce if desired.

Step 4

Add 8 ounces dried thin Chinese wheat noodles to the boiling water and cook according to package directions until tender. Meanwhile, coarsely chop 2 tablespoons roasted peanuts if desired.

Step 5

When the noodles are ready, drain and rinse under cold water until cooled. Drain again, shaking off the excess water. Add to the sauce and toss until evenly coated. Garnish with the reserved scallion greens, peanuts, and 1 teaspoon sesame seeds if desired.