Toss the potatoes with 2 tablespoons olive oil and place in a large, shallow roasting tin. Place in a preheated oven, 220°C (425°F), Gas Mark 7 for 15 minutes, turning once.
Add the mushrooms, stem side up, thyme and garlic to the tin, drizzle over the remaining oil and season well. Place a little goats’ cheese on each mushroom and return to the oven for a further 5 minutes.
Add the cherry tomatoes and return to the oven for a further 5 minutes more until the potatoes and mushrooms are cooked through. Scatter over the pine nuts and serve with the rocket.