In a medium bowl, whisk together the coconut milk, chia seeds, maple syrup, vanilla extract, and salt until fully combined with no clumps.
Cover the bowl and refrigerate for at least 4 hours or overnight, whisking once after 30 minutes if possible to ensure even thickening.
While the chia pudding sets, peel the mangoes and cut the flesh into small cubes. Store in a separate container in the refrigerator.
Once the chia pudding has thickened to a spoonable consistency, give it a final stir to break up any clumps.
In clear glasses or jars, layer 2-3 tablespoons of chia pudding, then a generous layer of diced mango. Repeat the layers until the container is full, ending with mango on top.
Serve immediately or cover and refrigerate for up to 5 days. Top with toasted coconut, fresh mint, or a drizzle of honey just before serving.
