Begin by preheating your oven to 350°F (175°C). This ensures your cookies bake evenly.
In a mixing bowl, cream together the softened butter and brown sugar until the mixture is light and fluffy.
Beat in the large egg and vanilla extract until well combined.
Stir in the thoroughly drained crushed pineapple until well-mixed.
In a separate bowl, whisk together the all-purpose flour, baking powder, baking soda, and salt. Gradually add the dry mixture to the wet ingredients, stirring until just combined.
If using pecans, fold them into the dough at this stage.
Using a cookie scoop or tablespoon, drop mounds of dough onto a baking sheet lined with parchment paper.
Bake in the preheated oven for 12-15 minutes, or until the edges are golden brown.
Allow the cookies to cool on the baking sheet for a few minutes before transferring them to a cooling rack.
Once completely cooled, you can drizzle with vanilla icing if desired.