Step 1

In large bowl, whisk together avocado oil, oyster sauce, and water to make marinade. Add sliced flank steak to bowl and coat with marinade. Cover bowl and marinate steak 30 minutes.

Step 2

Toward end of marinating time, whisk together soy sauce, sugar, and rice vinegar to make sauce. Set aside.

Step 3

After 30 minutes, remove steak from marinade and transfer to another large bowl. Add cornstarch and toss or stir to very lightly coat steak.

Step 4

In large frying pan or wok, heat ¼ cup neutral oil over medium-high heat. When hot, add steak, being careful not to overcrowd the pan. Work in batches if necessary. Cook steak until brown and crispy on each side.

Step 5

Remove steak from pan and set aside. Drain pan, leaving 2 tablespoons of oil. Add ginger to oil and cook until fragrant, approximately 1 to 2 minutes. Stir occasionally to prevent sticking or burning.

Step 6

Add sliced shallots and minced garlic to frying pan. Cook until fragrant, approximately 1 to 2 minutes, then add Fresno peppers. Cook approximately 30 seconds to 1 minute. Stir occasionally to prevent sticking or burning.

Step 7

Add chopped green and red bell peppers and cook 2 to 3 minutes, until peppers soften slightly. Stir occasionally to prevent sticking or burning.

Step 8

Return flank steak to frying pan. Pour in sauce, then add scallions. Stir to coat. Cook until sauce is completely absorbed.

Step 9

Serve hot on its own or with rice.