To make frozen watermelon cubes, cut a large watermelon in half and remove the rind. You can use half the watermelon for a few drinks, or the whole watermelon for more (save some fresh pieces for a garnish). Now cut into 1-inch pieces.

Place watermelon pieces on a non-stick baking tray (make sure it fits in your freezer). I lined it with wax paper for easy cleanup. Place pieces about 1" apart so they don't stick together. Freeze for 3-4 hours.

When you are ready to make the cocktails, place drinking glasses in the freezer to chill. Place the frozen watermelon, ice, tequila, orange liqueur, lime juice and agave into a high-speed blender. Blend until smooth. If your blender is stuck, you can move everything around a bit with a tamper. You can also add a few splashes of water or fresh watermelon to get things moving.

Taste the mixture and add more lime, agave or tequila if needed. If the mixture is too thin, add a few more pieces of frozen watermelon or ice and blend.

Spread a bit of salt or sugar on a small plate. You can also mix equal parts chili powder and salt together to add a little kick. Rub each chilled glass with a lime wedge. Dip the rim into the salt at a 45-degree angle and turn gently, until glass is coated (this avoids too much salt going into the glass).

Pour the frozen mixture into each glass, being careful not to disturb the prepared rim. Fill about ¾ of the way. Garnish with a piece of fresh watermelon, lime wedge and a sprig of mint. You can also place a piece of frozen watermelon on top for fun. CHEERS!