Rub the chicken with some olive oil, season with salt and pepper, then place in baking tray with enough room so there is gaps around them, then put in the oven.
Bake for 15 minutes, scatter the garlic cloves (reserve one and dice it while cooking the chicken) around the chicken, return to the oven and bake for another 30-35 minutes until the chicken is tender.
When done, remove the chicken to a plate and cover with foil, then a teatowel.
Drain the juice from the oven tray and reserve it.
Heat up a frying pan and fry the reserved, chopped, clove of garlic in some oil (about a tbsp), then add the mushroom, and the reserved juices and saute until tender.
Serve the chicken drumsticks on a bed of rocket (one handful per person), with the mushrooms on the side, a lemon wedge, and scatter the roasted garlic around it.