Place the potatoes into a saucepan and cover with cold water then bring to the boil and cook for 8-10 mins until tender then drain and lightly crush with a the back of a fork.
Cut the fennel in half and drizzle with half the oil and drizzle the other half over the fish.
Heat the BBQ, then add the fennel flat side down and cook for 4-5 minutes the turn over and continue to cook until tender.
Place the seabass skin side down on to the BBQ and cook for 4 minutes then turn over and cook for 1 minute more then remove from the BBQ.
Chop the herbs and add to the Colman’s Tartar Sauce then stir through the potatoes. Spoon on to a plate and sit the fish on top along with the fennel and a lemon wedge.