Pre-heat oven to 220°C conventional (or 200°C fan-forced) and line two oven trays with baking paper.
Lay out potatoes, zucchini, capsicum and eggplant slices on trays, spray with oil and season with salt and pepper.
Roast for 20-30 minutes until vegetables are softened (check vegetables after 20 minutes and remove any that are cooked).
While vegetables are roasting, heat a frying pan on medium heat and cook the haloumi slices 1-2 minutes on each side until golden and the cheese is melted. (Do this 5 minutes before vegetables are ready to serve).
Make four vegetable stacks, layering eggplant, potato, zucchini, haloumi, basil leaves and red capsicum.
Continue layering vegetables, cheese and herbs and serve with a drizzle of olive oil and a few olives on the side.