Preheat oven to 180°C. Line a baking dish big enough to fit all the mushrooms in a single layer.
Remove the stalks from each mushroom and place into the lined baking dish. Drizzle with the EVOO.
Place parmesan into the Thermomix bowl and mill *10 sec/speed 10. Remove from bowl and set aside.
Place the garlic into the Thermomix bowl and chop 2 sec/speed 5.
Add pesto and ricotta and stir 6 sec/Reverse/speed 1.
Divide between mushroom cups and sprinkle with the milled parmesan.
Bake 20 minutes or until the cheese is golden and the the mushrooms are softened. If you need to use a grill function to finish these off, do so but only for a few minutes.
To serve, drizzle with additional pesto and garnish with a small basil or oregano leaf. (Sage also works well!)