Preheat the oven to 350°F (175°C). Lightly coat a large loaf pan with non-stick baking spray and set aside.

In a mixing bowl, whisk together the flour, baking soda, baking powder, and a pinch of salt. Set aside.

In a large separate bowl, combine the granulated sugar with the cooled, melted butter, whisking until the mixture becomes smooth and creamy.

Beat in the egg until the mixture is well-blended.

Add in the crushed pineapple along with its juice (excluding the reserved amount for glaze), the sour cream, and the vanilla extract. Whisk together until a smooth, cohesive batter forms.

Gently fold the dry ingredients into the wet mixture, stirring only until no visible streaks of flour remain. Take care not to overmix the batter.

Transfer the batter to the prepared loaf pan and smooth the top. Bake in the preheated oven for 55–65 minutes, or until a toothpick inserted into the center of the loaf comes out clean. If the top begins to brown too quickly during baking, loosely cover it with foil and continue baking.

Once baked, remove from the oven and allow the bread to rest in the pan for 10 minutes on a wire rack. Then, gently remove the loaf from the pan and let it cool completely on the rack before applying the glaze.

In a small bowl, mix the sifted powdered sugar with the reserved pineapple juice until the mixture becomes smooth and pourable.

Drizzle the glaze generously over the cooled bread and allow it to set slightly before slicing.