Thai Nam Jim Pae 

1/4 cup garlic, chopped
1 tablespoon khing (root ginger), chopped
1 tablespoon horseradish, chopped
3/4 cup prik ki nu daeng (red birdseye chilies), chopped
1/4 cup prik ki nu (green birdseye chilies), chopped
1/4 cup lime juice
2 tablespoons fish sauce
1 tablespoon palm sugar

Grind the garlic, ginger and horseradish to a fine paste in a mortar
and pestle.  Add 3/4 cup red chilies, and 1/4 cup green chilies,
and pound until thoroughly integrated.

Add the lime juice, fish sauce, and sugar and continue to pound
until fully combined into a slightly liquid consistency.  If not
sufficiently liquid, add more lime juice and fish sauce keeping
the proportions the same.

Allow to stand for 1 hour before serving.

This will keep for two or three days in a well stopped container
in the refrigerator, but does not lend itself to freezing.