Preheat the oven to 200°C.
Coats the teal breast with olive oil and season with salt and pepper.
Sear the teal in an ovenproof frying pan for 2-3 minutes per side.
Transfer the pan to the oven and roast for 8 minutes until cooked through.
Remove the teal from the oven and let it rest for 2 minutes.
Simmer the teal bones, stock cube, wine, garlic, vinegar, and water in a saucepan for 10 minutes.
Whisk butter into the sauce and strain into a gravy boat.
Boil the sweet potato in water for 10 minutes until soft.
Drain the potato and mash with butter, soy sauce, and black pepper until smooth.
Place the mash on a plate, top with sliced teal, and pour over the jus.