Black Pepper Beef

Thinly slice the sirloin and marinate with oyster sauce, corn starch, and black pepper. Let sit while you prep the rest of the ingredients.
In small bowl, mix together sauce ingredients and set aside.
Heat wok or skillet over high heat. Line up all of your ingredients near the wok so that everything is ready to go.
Once the wok is hot, drizzle with oil.
Saute onions and bell peppers until soft. Remove and set aside.
Saute beef and garlic until beef is cooked.
Return onions and peppers.
Add sauce. Toss to coat.
Serve and enjoy!