In a medium heatproof bowl, stir together the red-pepper flakes, soy sauce and sesame oil; set next to the stovetop.
Bring a large pot of salted water to boil.
Meanwhile, in a large skillet, over medium heat, cook the 1/2 cup oil, peanuts and orange rind, shaking the pan occasionally, until the peanuts are golden and bubbling; 3 to 5 minutes.
Immediately pour the contents of the skillet over the red-pepper mixture; set aside.
Meanwhile, in the same skillet, heat the remaining tablespoon oil over medium-high heat..
Add the chicken; press it down, with a wooden spoon, into a thin layer.
Season with salt and a generous amount of black pepper; cook, without stirring, occasionally pressing the layer of chicken down, until the bottom is browned; 5 to 7 minutes.
Break the chicken up into small pieces and cook, stirring occasionally, until cooked through; 1 to 2 minutes more.
While the chicken cooks, cook the noodles according to package directions, until chewy but not soft.
Drain; toss with a bit of sesame oil.
Remove and discard the orange rind from the chili oil.
Off the heat, add enough chili oil to coat the chicken and stir, scraping up any browned bits from the pan.
Add the noodles and toss, adding more chili oil to fully coat the noodles and chicken; if you don't use all of the chili oil, store in the refrigerator for 2 weeks in an airtight container.
Top with chives and serve at once.
