Before beginning, let your concentrates melt in the fridge.

Combine the lemon and lime concentrate in a large mixing bowl. Add the powdered sugar - I recommend sifting it first, this will make the whole process a little easier.

When you're ready to serve, put the frozen mixture into a punch bowl or pitcher.

Add the sprite (and tequila, if you want) and mix well. The texture should be slushy but combine fully with the Sprite. I always add ice to keep it cold for hours, and mix in lime slices.