Preheat the oven to 375°F. Spray a muffin pan with baking spray.
Whisk flour, sugar, baking powder, and salt together in a large bowl.
2 cups (282g) all-purpose flour, 3/4 cup (150g) granulated sugar, 2 1/2 teaspoons baking powder, 1/2 teaspoon salt
Whisk melted butter, eggs, milk, and vanilla in a separate bowl. Add to the flour mixture and stir gently just until combined.
1/2 cup salted butter, 2 large eggs, 3/4 cup milk, 1 teaspoon pure vanilla extract
Stir in pineapple and 3/4 cup of the coconut.
1 1/2 cups pineapple tidbits, 1 1/2 cups shredded sweetened coconut
Divide batter evenly into muffin cups. Sprinkle with the remaining coconut.
Bake for 22-25 minutes until done.