Pre-heat oven to 190C/fan 170C/gas 5.
In a small saucepan, bring 500ml water, ½Tsp sea salt and 1Tbsp oil to boil.
Add toasted buckwheat into boiling water and cover saucepan with a lid. Bring to gentle simmer in low heat. Cook until water is absorbed, about 12 to 15mins. Remove from heat and cover the pot with a lid for 10 mins to allow the buckwheat to steam in pot.
While buckwheat is steaming, cut out the top of the pumpkin & keep it aside. Remove strings and seeds. Scoop 1 cm into the flesh with a spoon, chop roughly and reserve.
Heat a large saucepan or wok over medium to high heat. Add 2Tbsp oil into pan, add onions and sauté till opaque. Then add garlic and carrots and cook for 3mins.
Next, add diced sausages, mushrooms, tomatoes, reserved chopped pumpkin, black pepper and Italian herbs. Cook over medium high heat till fragrant for about 4mins.
Add cooked buckwheat and Lee Kum Kee Sauce with 4Tbsp of water. Stir everything well. Cook for another 3mins.
Place pumpkin on a roasting pan. Then ladle the buckwheat mixture into pumpkin and place pumpkin lid next to pumpkin on the pan. Brush outer pumpkin and lid with 1Tbsp of oil.
Roast for 45 mins to 1hr or until pumpkin flesh is tender.
Garnish with grated cheese and return to oven for 3mins. Serve with Pumpkin lid on.