"A fun, inventive take on the traditional Brazilian caipirinha. The açaí gives it a good depth of flavor. I used the frozen açaí pulp, defrosted. I also make caipirinhas with just red grapes and it's delicious too."
Place grapes and sugar into a glass; mash well with a cocktail muddler. Fill the glass with ice cubes. Pour in cachaca and (defrosted) acai pulp; stir well. You can also shake the cocktail in a cocktail shaker.