Cook the noodles in large pot of boiling unsalted water over medium heat until barely tender and still firm, about 3 minutes. Drain immediately and rinse with cold water until cold. Drain the noodles really well and transfer to a wide bowl; toss with the sesame oil so they don't stick together.
In the same pot, heat the peanut oil over medium low heat. addd green onions, ginger, garlic, and chile paste.
Cook, stirring, until vegetables are softened, only about a minute or so.
Then stir in brown sugar, peanut butter, vinegar, soy sauce, and hot water. Stir until the sugar has dissolved and peanut butter is smooth. Toss noodles back into pan and coat with sauce.
Toss sesame seeds in a dry skillet over medium low heat until golden brown. Shake the pan constantly to keep them from burning. Put noodles in a serving bowl and garnish with sesame seeds, cilantro and cucmber strips. You can place the sauced noodles in the refrigerator and serve them cold; just garnish right before serving.