Preheat your oven to 350°F (175°C). Grease a muffin tin or line with paper liners.
In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.
In another bowl, mix the coconut milk, vegetable oil, and eggs until well combined.
Pour the wet ingredients into the dry ingredients and stir until just combined. Do not overmix.
Fold in the diced mango and shredded coconut.
Divide the batter evenly among the muffin cups.
Bake for 20 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Let the muffins cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.