In a small bowl, mix together the oyster sauce, soy sauce, and cornstarch. Stir until well combined and set aside.
Heat 1 tablespoon of cooking oil in a wok or large skillet over medium-high heat.
Add the shrimp to the pan in a single layer. Cook for about 2-3 minutes on one side until they turn pink and opaque. Flip the shrimp and cook for an additional 1-2 minutes. Remove the shrimp from the pan and set aside.
Add the remaining tablespoon of oil. Toss in the minced garlic, grated ginger, and the white parts of the green onions. Stir-fry for about 30 seconds until fragrant.
Toss in your choice of thinly sliced bell peppers, broccoli florets, or snap peas. Stir-fry for about 3-4 minutes until the vegetables are vibrant and tender-crisp.
Return the cooked shrimp to the pan and pour the prepared sauce over the mixture. Stir well to coat everything evenly and cook for an additional minute until the sauce has thickened slightly.
If you’re using fresh cilantro, add it now and give everything a good toss.
Serve over steamed rice or noodles.