Green Turtle Soup

1. Trim the turtle meat and cut it into small dice. Simmer it gently in the stock for about 1 hour, until completely tender, skimming the surface as needed, then lift out the meat and reserve the strained stock.
2. Finely chop the onion. Melt the butter in a heavy pot over medium heat, soften the onion without colouring it, then stir in the flour and cook the roux for 2 to 3 minutes until it smells nutty.
3. Gradually whisk in the reserved hot stock so no lumps form, and let the soup come to a gentle simmer, stirring, until it thickens slightly.
4. Return the diced turtle meat to the pot and add the oyster liquor, ground mace, cayenne and sugar, then simmer gently for 15 minutes to marry the flavours.
5. Press the hard-boiled egg yolks through a fine sieve and stir them into the soup to enrich and lightly thicken it.
6. Add the sherry and a squeeze of lemon juice, then taste and season with salt and a little more cayenne if you like it sharper.
7. Ladle into warmed bowls and serve at once, with thin slices of lemon offered alongside.

You'll use: Large pot · Saucepan · Whisk