Heat the sesame oil in a wok over high heat. Add the tomatoes and stir-fry for two minutes. Add the venison, leek and capsicum. Stir-fry for a further 6 minutes, stirring frequently; then add the soy sauce and cook for a further 3 minutes. Season with salt and pepper to taste.
To make the dressing, mix sweet chilli sauce, olive oil and sesame oil together in a small bowl.
To serve, place venison and vegetables on a serving platter and drizzle with the dressing. Serve with rice or noodles.