I’ve got a recipe in my notebook for something along these lines which dates back probably 15-20 years. I‘m quite convinced it was a recipe of Mary Berry’s, but I don’t have any way of confirming this.
In a sense this is barely a recipe - rather a suggestion or idea. It’s just that crab and avocado go very well together. So do both with certain herbs, amongst which are dill, chervil, tarragon, parsley and chives. Observe the last four of these and we’re back to fines herbes, which was the basis of a previous crab recipe - Crab Omelette “aux Fines Herbes”. You could use any combination of these herbs to good effect but here I have zeroed in on dill and chive - both in the avocado mix, and in the dressing. I’ve used a technique of Michel Roux to create a herb oil which I’ve embellished with some lemon, sugar and salt resulting in a dressing which compliments the dish admirably.
Because each component in this dish can be prepared ahead of time this is a really easy, very satisfying, and quite eye-catching dinner party starter. And if you’re feeling particularly flush, you could use lobster instead of crab.
In essence this is a development of a prawn cocktail. All that is going on here is a mix of avocado and cucumber with some herbs and seasoning, and a crab 'cocktail' built out of the traditional ingredients. Layer up in a ring-mould with some salmon roe on top and that's it - job done! You can add a pinch of curry powder or Chinese Five-Spice to the crab mixture for an extra aromatic hit.
The quantities given are quite approximate - you can adjust them according to your preference.
Crab and Avocado Tian
Ingredients (Approximate quantities for 2 servings)
For the avocado and cucumber:
1 ripe avocado, cut into 5mm dice
Cucumber, 3 tbsp of 5mm dice
1 tbsp finely chopped chives
1 tbsp finely chopped dill
Extra virgin olive oil
½-1 tsp finely grated lemon zest
1 tsp (approx) lemon juice
Salt and freshly ground black pepper
For the crab 'cocktail':
100g white crab meat
1 tsp tomato ketchup
2-3 tsp mayonnaise (ideally home-made)
A few drops of Worcestershire sauce
A drop or two of Tabasco
Pinch of freshly grated nutmeg or ground mace
Pinch of curry powder or Chinese five-spice (optional)
Salt and freshly ground black pepper
To finish:
3 tbsp (approx 30-40g) salmon roe
Finely chopped chives, for garnish
Olive oil (to grease the ring-mould)
Herb dressing (optional, see Note)
Method
In a bowl, mix the avocado, cucumber, lemon zest and herbs. Add a splash of extra virgin olive oil, a dash of lemon juice and some seasoning. Taste and adjust accordingly. This can be refrigerated for a few hours, but bring back to room temperature before using.
In a second bowl, mix the crab meat, ketchup and mayonnaise. Add the Worcestershire sauce, Tabasco, nutmeg or mace, curry powder or Chinese five-spice (if using) and seasoning to your taste. This can be kept in the fridge for a day without harm. Allow to come to room temperature before using.
To serve the dish, oil the inside of the ring-mould with olive oil. Put the mould on a serving plate and layer half the avocado and cucumber mix, half the crab 'cocktail' and then half the salmon roe, finishing with a sprinkling of finely chopped chives. Release the stack from the mould and drizzle the plate with the herb dressing, if using. Repeat with the second plate and serve straightaway.
Notes
Herb dressing: To make the herb oil, heat 100ml of good quality olive oil (not extra virgin) to 100°C. Add 10g chives and 10g dill. Allow to cool, then blitz in a blender and pass through a sieve. To create the dressing add a splash of lemon juice and season with salt and caster sugar to taste. Refrigerate until ready to use.
References
"Sauces, Savoury and Sweet", Michel Roux (2009), pp. 121-2: https://www.amazon.co.uk/Sauces-Savoury-Sweet-Michel-Roux/dp/1844006972
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