Pea-shoot sauce

Ingredients

(makes 600-700ml, serves about 10)

250ml coconut milk
250ml chicken stock
3 lemon grass stalks, bruised
2-3 red chillies, split
8 lime leaves
30g butter
30g shallots, finely diced
1tbs tarragon, chopped
500g pea shoots, including the leaves
2tbs nam pla (bottled Thai fish sauce), or to taste

Method

Put the coconut milk, stock, lemon grass, chillies and lime leaves in a pan (1). Leave on the side of the range for 30 minutes. Heat but don't boil. The liquid base should absorb flavours without cooking out. Strain the liquid and reserve.

Melt the butter in a fresh pan. Add the shallots and sweat without colouring until softened.

Add the tarragon and pea shoots (2). Turn up the heat and stir them until they've wilted like spinach - about two minutes.

Pour over the reserved sauce base (3). Boil and simmer for two minutes.

Empty the sauce into a liquidiser. Blend until the emulsified sauce takes on a deep chlorophyll colour. Pass it through a fine sieve (4). Add nam pla.

The sauce can oxidise and lose its intense colour if it's not cooled (5).

Leave pan or container in which it's kept over a bowl of ice until cool.