Prepare the Chicken: In a large skillet or wok, heat the vegetable oil over medium-high heat. Once hot, add the sliced chicken breast to the skillet. Stir-fry for 5-7 minutes, or until the chicken is cooked through and golden brown.
Add the Aromatics: Add the minced garlic and grated ginger to the skillet. Stir continually for about a minute until fragrant.
Incorporate the Veggies: Toss in the sliced red and yellow bell peppers, broccoli florets, and snap peas. Stir-fry for another 3-5 minutes until the vegetables are vibrant and tender-crisp.
Add the Sauce: Pour the sweet chili sauce and soy sauce over the chicken and vegetables, stirring to coat everything evenly.
Thicken the Sauce: Stir in the cornstarch mixture and continue to cook for 1-2 minutes until the sauce thickens and glistens.
Serve: Remove from heat and serve immediately over rice or noodles.