In saucepan over high heat, heat prawn with head fat to break, then blend heat fat with egg yolk and cooked prawn to emulsify.

In medium sacepot over medium heat, heat milk, prawn cream, sugar, caramelized fish sauce, and coconut vinegar, bring to low simmer, then remove from heat.

In medium mixing bowl, whisk to temper hot cream mixture into egg yolk mixture, then return to saucepan, stir continuously to lightly thicken ice cream base to 90°C, pass through chinois, then cool in ice bath, taste and adjust as needed, freeze in pints for service.