Preheat your oven to 350°F (175°C). Line a muffin tin with paper liners.
In a large bowl, whisk together the flour, sugar, coconut flakes, baking powder, and salt.
In another bowl, mix the vegetable oil, eggs, and vanilla extract until well combined.
Pour the wet ingredients into the dry ingredients and stir until just combined. Fold in the diced mango.
Divide the batter evenly among the muffin cups.
Bake for 20-25 minutes, or until a toothpick inserted into the center comes out clean.
Let the muffins cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.