Preheat the oven to 200C/400F/Gas 6.
Place the mushrooms onto a non-stick baking sheet, sprinkle over the garlic and parsley and drizzle with oil. Season well with salt and freshly ground black pepper.
Transfer to the oven and bake for 8-10 minutes, or until the mushrooms start to soften.
Remove from the oven and place equal amounts of Stilton onto each mushroom. Return to the oven for another 3-4 minutes, or until the cheese has melted.
To serve, place the mushrooms onto serving plates and garnish with parsley and lemon wedges.