Peel the red onions and cut into chunky wedges.
Slice the red pepper into thick slices.
Drain the tin of potatoes and pat dry.
Cut the corn cobettes in half.
Put the red onions, red pepper, potatoes and corn cobettes in a large mixing bowl with the remaining ingredients.
Season well with salt and black pepper.
Preheat the oven to 200°C, fan 180°C, gas 6.
Line your largest baking tray with baking paper.
Tip the contents of the bowl onto the prepared tray and roast for 35-40 minutes, until golden.
To freeze: Add the raw ingredients in the mixing bowl to a large labelled freezer bag and freeze flat.
Cooking from frozen: Remove from the freezer and allow to fully defrost. Once defrosted, cook as instructed.
