Dartmouth crab salad

Method

1. For the tarragon vinaigrette: mix the lemon juice, vinegar and sugar with some salt and pepper in a bowl. Gradually whisk in the olive oil. Using a small funnel, pour the dressing into a jar or bottle and drop in the garlic and tarragon sprig. Set aside for the flavours to infuse.

2. For the salad: Pull off the claws and legs from the crab and carefully crack them open. Remove the white meat, picking it out carefully and trying to prevent any shell from falling into the meat. Set aside. Turn the crab over onto its shell and pull the middle back to expose the inside. Discard the gills and scrape all the dark meat into a bowl. Set aside.

3. Mix the mayonnaise, ketchup, Worcestershire sauce, Tabasco and 1 tsp of the cognac. Stir together, add the lemon juice and refrigerate.

4. Halve the avocado and discard the stone. Cut each half into two and peel carefully. Thinly slice each quarter and place the slices in a bowl. Add 1 tablespoon of the tarragon vinaigrette and carefully turn the avocado pieces over with a spoon. Stir in the apple and shallot. Set aside.

5. For each serving, place a 5x6cm ring mould in the centre of each plate. Spoon a quarter of the avocado salad into the mould and press it down gently. Stir the remaining tsp of cognac into the dark crabmeat. Season with salt and lemon juice and spoon a quarter of it over the avocado. Season the white meat with a little lemon juice and press a quarter of it down over the dark meat. Remove the mayonnaise mixture from the fridge and drizzle a dessert spoonful of it over the white meat. Sprinkle over 1/4 teaspoon of the curry powder. Gently remove the mould. Repeat for remaining three servings.

6. Cut the grapefruit segments in half lengthways and arrange a few around the base of each crab salad. Scatter some rocket leaves around the edge of each plate, then place a few cherry tomato halves around the edge also. Dot a little more of the vinaigrette between the tomato halves. (The remaining dressing will keep in the fridge for several days.) Garnish the top of each salad with a piece of crab claw if you like.