This is an optional step but highly recommended to improve the flavour and colour of your curry. In a mortar and pestle, pound julienned Thai basil into a fine paste1 teaspoon. Add grachai and pound into a paste. Add the shrimp paste and green curry paste3 ½ Tablespoons and pound to mix. Alternatively, you can add the basil, grachai, and shrimp paste to a blender, and blend it with some of the chicken stock1 cup until smooth, and you'll just need to pour this into the curry with the rest of the stock.