Thank you, Food52! I don't think this cold terrine would ever have come out of my kitchen without your avocado challenge...I adore avocado and wanted to highlight its green creaminess and pay to tribute to classic avocado Ritz as well as the wonderful wobbliness of 60's and 70's gelatin mousses...Then I remembered a summer fruits terrine I used to make, set in jelly. And so this avocado, mango and shrimp aspic evolved, with a hint of SE Asia and a kick of spice. Perfect picnic food, buffet offering, and cool starter to summer supper.
The mango and shrimp pieces should be small enough to be incorporated within a slice. If they are larger, it becomes hard to cut neatly. The avocado can be larger, as it is easy to slice through.
You can use leftover shrimp from a barbecue or cocktail, or start from scratch, following the first part of this recipe. To turn it vegan, substitute carrageenan or agar-agar for gelatin and omit the shrimp.
In a bowl, toss cleaned shrimp tails with all the ingredients of the marinade and leave for a minimum of an hour or up to three hours, to marinate.
Heat some non scented oil in a pan and pan fry the shrimp till pink. Remove.
Add the marinade ingredients to the pan and reduce till sticky. Pour over the shrimp and allow to cool.
When cool, slice each shrimp tail into 3-4 pieces, about 1/4" at most. Reserve.
For the terrine you need a 1.5 quart size pyrex or ceramic terrine mould.
In a small bowl combine the mango cubes with the 1/4 cup scallions, 4 Tbsps lime juice, salt and pepper and marinate for an hour. After an hour, strain the mango and reserve the marinade.
In a small bowl dissolve the gelatin in the 2/3's cup very hot water. When it has dissolved add the 1/3 cup lime juice, sugar, salt, fish sauce. Also add the reserved liquid from the mango. Allow the mixture to cool a little to tepid.
Add a single layer of avocado, with the pieces just about touching each other - bear in mind this will be the top of your terrine, once it is turned out.
Add a layer of mango cubes.
Sprinkle the scallions and all the mint across in a fine layer.
Add half the shrimp pieces.
Add more avocado and the rest of the mango.
Add the rest of the shrimp.
Add a final avocado layer (which will be the base of the terrine, when turned out).
Now pour the gelatin mixture carefully over the contents of the terrine. It should just cover the top layer of avocado.
Put a sheet of wax proof paper over the top and gently press down if the avocado is a little above the liquid surface. You could weigh it down with a couple of cans, or with dry baking beans.
Refrigerate until set, and up to two days (unscientific guesstimate), covered.
To unmould, slide a warmed knife around and down the edge of the terrine.
Place a board or large flat plate over the terrine and flip, shaking firmly until you hear plop!
If the terrine is stuck for some reason dip its base briefly in a basin of boiling water, and repeat.
To serve, slice with a very sharp small knife, point down, and catch the slices on a spatula or pie lifter.