You will need:
10 small flat mushrooms, wiped and stalks removed
4 cloves of garlic, peeled and crushed or grated
3 tablespoons olive oil
Salt and freshly ground black pepper
10 rocket leaves
1 tablespoon finely chopped pitted black olives
10 shavings of Parmesan cheese, using a peeler
Preheat the oven to 200°C, 400°F, Gas 6. Place the flat mushrooms on a baking tray, in a single layer. In a bowl, mix the garlic and the olive oil and season with salt and freshly ground black pepper. Spoon this garlic oil over each mushroom (about a teaspoon for each) and roast in the oven for 8-10 minutes or until they are cooked.
These can be allowed to cool to room temperature. To assemble, place the toasts on a large plate, top each with a rocket leaf, then a roasted mushroom, then a scattering of the chopped black olives. Top each with a Parmesan shaving and serve.