Step 1

Preheat the oven to 350°F.

Step 2

Place the cashews on a baking sheet in a single layer. Toast in the oven until fragrant, about 5 minutes. Set aside; they will crisp up as they cool.

Step 3

Meanwhile, prepare the sauce: in a small bowl, whisk together the water, cornstarch, hoisin sauce, and soy sauce. Set aside.

Step 4

Place the chicken pieces in a large bowl. Sprinkle with the salt and pepper and toss to coat evenly.

Step 5

In a large nonstick skillet, heat 1 tablespoon of the vegetable oil over high heat until very hot. Add half of the chicken to the skillet and stir-fry until lightly browned but not cooked through, about 3 minutes. Transfer to a plate.

Step 6

Add the remaining tablespoon vegetable oil to the skillet; then add the remaining chicken, garlic and white parts of the scallions. Stir-fry until the chicken is lightly browned but not cooked through, about 3 minutes. Return the first batch of chicken to the pan. Turn the heat down to medium and add the rice vinegar; cook until evaporated, about 30 seconds.

Step 7

Add the sauce mixture to the chicken; cook, tossing, until the chicken is cooked through and the sauce is nicely thickened, about 1 minute. Remove from the heat. Stir in the scallion greens, cashews and sesame oil. Serve immediately.