Mojito-inspired spinach, avocado, lime and mint smoothie recipe

This energising mint, creamy avocado and zesty lime smoothie is the perfect refreshing drink to win over any green-smoothie sceptic. Invite your friends over, serve up a double or triple batch of this green monster, and toast to glowing energy and health. If you are feeling wild, add a splash of sparkling water (and optional white rum) to make an alternative to a classic mojito.
Prep time: 8 minutes, plus overnight freezing time for the watermelon (optional)
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