Remove frozen dragon fruit from the freezer and let it rest 2 to 3 minutes. If your banana is not frozen, peel, slice, and freeze for at least 2 hours before starting; shake canned coconut milk vigorously for 30 seconds before opening.
Pour the coconut milk (1 cup / 240ml), lime juice (1/2 teaspoon), and honey (1 tablespoon) into the blender first. Adding liquid before the frozen fruit protects the blades and helps ingredients blend more efficiently.
Add the frozen dragon fruit (2 cups / 300g), frozen banana, frozen mango if using (1/2 cup / 75g), and pinch of salt on top of the liquid. Do not add extra ice, as the frozen fruit provides all the thickness and chill needed.
Secure the lid tightly, start on low for 10 seconds to break up large chunks, then increase to high and blend for 45 to 60 seconds until completely smooth. If the blender stalls, stop and use a spatula or tamper to push fruit toward the blades, then resume.
The smoothie should be thick enough to coat the back of a spoon but still pourable; if too thick, add coconut milk one tablespoon at a time, and if too thin, blend in a small handful of ice for 15 seconds. For a smoothie bowl, use only 1/2 cup coconut milk for an extra-thick result.
Pour into two chilled tall glasses and garnish with any combination of fresh dragon fruit slices, granola, sliced kiwi, coconut flakes, chia seeds, a honey drizzle, and fresh mint. Serve immediately for the best color, texture, and flavor.