1 pound boneless, skinless chicken thighs, trimmed of fat and cut into 1-inch pieces
1 tablespoon dry sherry or rice wine
2 teaspoons soy sauce
3 medium cloves garlic, pressed through garlic press or minced (about 1 tablespoon)
1/2inch piece fresh ginger, peeled and minced (about 2 teaspoons)
3 tablespoons peanut oil or vegetable oil
1/2 cup roasted unsalted peanuts
1 teaspoon dried red pepper flakes
3/4 cup low-sodium chicken broth
2 teaspoons black rice vinegar or plain rice vinegar
2 teaspoons toasted sesame oil
1 tablespoon oyster sauce
1 tablespoon hoisin sauce
1 1/2 teaspoons cornstarch
1 medium red bell pepper, cut into 1/2-inch dice
3 medium scallions, sliced thin
1. Toss chicken with sherry and soy sauce in medium bowl; marinate until thighs have absorbed flavors, about 10 minutes. Mix garlic, ginger, and 1 tablespoon oil in small bowl; set aside. Combine peanuts and chiles in small bowl; set aside. Mix chicken broth, vinegar, sesame oil, oyster-flavored sauce, hoisin sauce, and cornstarch in small bowl or measuring cup; set aside.
2. Heat 1 tablespoon oil in 12-inch skillet over high heat until just beginning to smoke. Add chicken and cook without stirring for 2 minutes, allowing chicken to brown on one side; stir and cook 1 1/2 to 2 minutes more, until no longer pink; stir peanuts and chiles into chicken and continue cooking until peanuts have darkened slightly, 30 to 40 seconds longer. Transfer chicken, peanuts, and chiles to bowl; set aside.
3. Return skillet to burner and reheat briefly, 15 to 30 seconds. Add remaining 1 tablespoon oil, swirl to coat pan, and add red bell pepper; cook, stirring occasionally, until slightly softened, about 45 seconds. Clear center of pan, add garlic-ginger mixture, mash into pan with spoon or spatula, and cook until fragrant, 10 to 15 seconds; stir into peppers until combined. Stir broth mixture to recombine, then add to skillet along with reserved chicken, peanuts, and chiles; cook, stirring and scraping up browned bits on bottom of pan, until sauce has thickened to syrupy consistency, about 45 seconds. Stir in scallions and serve.