First, wash and trim the leeks before finely slicing them and the brussels sprouts. Then, heat 1/2 tsp olive oil with 1 tsp garam masala in a casserole pan over a medium-low heat. Slowly add the vegetables and cook until softened.
Preheat oven to 200°c/180°c fan forced. Stir the couscous into the cooked vegetables and crumble in the feta. Season mixture with salt and pepper to taste. Then, line a baking tray with baking paper and place 2 filo sheets on the tray, making sure they are overlapping in the centre. Brush sheets with a bit of left over olive oil and top with a sprinkle of remaining garam masala. Repeat this process with the rest of the filo sheets.
Gently spread the onion relish over the filo stack and crumble the couscous and vegetable mixture horizontally down the middle. Start from one edge and then carefully roll the filo to encase the filling. Seal.
Transfer the log, sealed end down, to the baking tray. Drizzle with olive oil and garam masala before baking from 25-30 minutes. Serve and enjoy.
