Follow these simple steps to create your Spicy Stir-Fried Mongolian Chicken:

1. Prepare the Chicken: Thinly slice the chicken breasts and set them aside.
2. Make the Sauce: In a small bowl, mix together soy sauce, chili paste, brown sugar, cornstarch, and water. Set aside.
3. Heat the Oil: In a large skillet or wok, heat the vegetable oil over medium-high heat.
4. Cook the Chicken: Add the sliced chicken to the skillet and stir-fry for 5-7 minutes or until golden brown and cooked through.
5. Add Aromatics: Stir in the minced garlic and ginger, cooking for an additional 1-2 minutes until fragrant.
6. Add Vegetables: Toss in the sliced bell peppers and broccoli florets. Stir-fry for about 3-5 minutes until the vegetables are tender but still crisp.
7. Add the Sauce: Pour the prepared sauce over the chicken and vegetables. Stir well to coat everything evenly.
8. Simmer: Allow the mixture to cook for another 2-3 minutes, stirring occasionally, until the sauce has thickened.
9. Finish with Green Onions: Add the chopped green onions, mixing them into the stir-fry just before serving.
10. Garnish: Sprinkle with sesame seeds if desired.

Following these steps will help you create a vibrant and delicious dish that’s sure to impress your guests!