Heat oil in a wok or large skillet over high heat. Add venison and stir-fry for 1 – 2 minutes, remove venison from pan. Add ginger and garlic to pan and cook 30 seconds. Add soy sauce, beef broth, hoisin sauce, rice vinegar, green onions and mushrooms. Heat to a boil and then cook for 2 minutes. Stir in cornstarch mixture, a little at a time to thicken sauce (you may not need all of the cornstarch). If sauce gets too thick, thin with additional beef broth or soy sauce. Stir in snow peas and return venison to pan. Cook for 1 minute more. Gently fold in tomato and sprouts and cook for 30 seconds to warm. Spoon over warm rice.