Preheat your oven to 350°F (175°C) and line two baking sheets with parchment paper.

In a large mixing bowl, cream together the softened unsalted butter with granulated sugar and brown sugar using an electric mixer until light and fluffy, about 3-4 minutes.

Add in one egg to the creamed mixture and beat until fully incorporated.

In a separate bowl, whisk together the all-purpose flour, baking powder, and salt. Gradually add this dry mixture to the wet ingredients, mixing just until combined.

Gently fold in the crushed pineapple ensuring it is evenly distributed throughout the dough.

Scoop portions of the dough and flatten them slightly in your palm, placing them on the lined baking sheets, spaced about two inches apart. Press a pineapple ring and a maraschino cherry into the center of each cookie.

Bake for 10-12 minutes, until the edges are lightly golden and the centers appear set.

After baking, let the cookies cool on the baking sheets for about 5 minutes before transferring to a wire rack to cool completely.