1/4 lb palm sugar, coarsely chopped
1/4 cup Thai fish sauce
1 oz seedless tamarind pulp (paste)
1 1/4 cup water
1 tablespoon cayenne pepper
Combine the palm sugar, fish sauce, tamarind pulp, and water in a medium pot. Set the pot over high heat, bring the mixture to a boil, then immediately decrease the heat to maintain a simmer.
Use a whisk or spoon to break up the palm sugar and tamarind pulp as they soften and cook just until the tamarind has fully softened and dissolved into the mixture, 5 to 8 minutes.
Stir in the cayenne, turn off the heat, and let the mixture sit, stirring occasionally, until it has cooled to room temperature. Use immediately or refrigerate for up to a week.