Step 1

Preheat oven to 450 degrees F. Spray a large, rimmed baking sheet with cooking spray (if desired, line with foil first for easy cleanup). Set aside.

Step 2

In a small bowl, whisk together soy sauce, garlic, brown sugar, ginger, and pepper. Set aside.

Step 3

Place beef, bell peppers, and onion in a single layer on the prepared baking sheet.

Step 4

Pour half of the sauce (about 1/3 cup) over top and toss to coat.

Step 5

Roast beef and vegetables for 10-14 minutes, or until beef is cooked to desired doneness (about 145 degrees F for medium-rare). Toss with reserved sauce.

Step 6

Garnish with sesame seeds and sliced green onions. Serve over rice, if desired.