Cut the peppers in half and remove the cores, place cut side up on a baking sheet and set aside.
Heat the oil in a large pan and gently sauté the onion for 3 to 4 minutes until softened, add the mince and cook until browned breaking up the mince as it cooks.
Stir in the garlic and spices and mix well.
Add the bulghar wheat and stock and bring gently to a simmer. Allow to simmer gently for 15 minutes until the bulghar is soft and most of the stock has been absorbed.
Meanwhile preheat the oven to 190°C/180°C fan/gas mark 5. Divide the bulghar mixture equally between the peppers and bake for 25 minutes until the peppers are tender.