IF you've never had Scotch egg with duck leg and flaked grey mullet in with the sausage meat, head for The Merchant House in Hertford. It's one of executive chef Geoff Mastro's contributions to the new Great British Classics menu and exactly in line with his philosophy of keeping things simple but with strong flavours to maintain the essential excitement of eating out.Says Geoff, 'I'm a believer in not having too many combinations on the plate because the flavours I do have on there are enough to bring the dish up.'The Classics offering is one fresh arrival at The Merchant House; another is a new a la carte collection that will run through May and June with lots of spring dishes to take account of the season. A typical entry is Geoff's sea bass recipe which, again, starts simple but then adds the puree and seaweed - stocked by most supermarkets - for something different.With everything from ice cream to bread made on the premises, a growing wedding business and a dessert list reflecting Geoff's training in pastry to add to the varied dishes on offer, The Merchant House is well on track to achieve its ambition to be Hertford's fine-dining flagship.Ingredients (serves 4)4 fillets sea bass1 sweet potato1 bunch of watercresssalt and pepper1 tbsp olive oil4 sheets of Nori dried seaweed20g sea salt1 tbsp olive oilMethod- Peel the sweet potato, dice and then place into boiling salted water. Bring to the boil and cook until soft. Drain off the water, add salt and pepper then place the sweet potato into a blender and blitz until smooth. Place the watercress in boiling water, leave for just 10 seconds then drain off and squeeze all the excess water out so it is as dry as possible. Add salt and pepper then place the watercress in a blender and blitz until smooth- Place the seaweed on a greased baking tray and sprinkle the olive oil and sea salt on top. Place in a cool oven (120 deg C) for about 5 minutes. When slightly warm, cut into thin strips (this can be done in advance)- Place a little olive oil in a non-stick pan and place on a medium heat. Place the sea bass in the pan skin side down first and gently colour both sides.- To present, spoon the sweet potato pur�e in the middle of the plate, then place the sea bass on top. Spoon the watercress pur�e on top of the sea bass and finish with strips of seaweed and a drizzle of olive oil.Book a tableThe Merchant House21 St Andrew StreetHertford SG14 1HZ01992 504504www.themerchanthouse.co.uk