Heat 1 tablespoon canola oil over medium high heat in a wok or skillet.
Add the prepared onions and peppers to the hot oil and season with salt and pepper; cook for 5 to 6 minutes, or until tender. Stir in the garlic, and continue to cook for 30 seconds, or until fragrant.
In the meantime, prepare the sauce by mixing together soy sauce, rice vinegar, sesame seed oil, beef broth, sugar, ginger, and corn starch.
Remove veggies from the skillet and set aside; keep covered.
Add the rest of the canola oil to the skillet and raise heat to high; add steak, season with salt and pepper, and cook for 2 minutes per side.
Stir the vegetables back in the skillet and pour in the sauce; stir and continue to cook for 1 to 2 more minutes, or until heated through and sauce has started to thicken.
Remove from heat, garnish with green onions, and serve over rice or cauliflower rice.