In a small saucepan, combine the tamarind paste and hot water. Stir to dissolve the paste. Add the remaining ingredients and stir to combine.Pour into a small saucepan and bring to a boil and simmer at medium-high heat, stirring constantly until the sauce has thickened (or 5-10 minutes).
Serving or storing
Remove the sauce from the heat and let it cool for a few minutes. Pass the sauce through a fine-mesh sieve to discard all solids.Use to brush meats for grilling or serve alongside your barbecue. To store, pour the sauce into an airtight container and store in the refrigerator or freezer for up to a month.