- Step 1
Place sugar and water in a heatproof bowl. Stir until sugar dissolves. Place in the fridge for 30 minutes to chill.
- Step 2
Place the lime juice in a small bowl. Place the extra caster sugar on a plate. Dip rims of 4 martini glasses into the juice, then into the sugar to coat.
- Step 3
Place the sugar syrup, strawberry, ice cubes, tequila, Cointreau and remaining lime juice in the jug of a blender and blend until smooth.
- Step 4
Divide the margarita among prepared glasses and serve.