Heat the olive oil in a large pan over medium-high heat.
Add the minced garlic and minced ginger. Stir and cook for about 30 seconds until fragrant.
Add the thinly sliced chicken breasts. Cook for 5–7 minutes, stirring often, until the chicken is fully cooked.
Add the sliced red bell pepper, yellow bell pepper, and green bell pepper. Stir everything together and cook for 3–4 minutes until the peppers are slightly tender but still crisp.
Pour in the soy sauce and oyster sauce. Stir well so the chicken and bell peppers are evenly coated with the sauce.
Season with salt and black pepper to taste. Mix everything well.
Cook for another 2–3 minutes, stirring occasionally, until everything is hot and the sauce lightly coats the chicken and vegetables.