Preheat oven to 350°F (180°C) and line two baking sheets with parchment paper.

In a large bowl, cream the softened butter and sugar together for 2 to 3 minutes until light and fluffy.

Add the egg and vanilla extract, beating until smooth and well combined with no streaks remaining.

In a separate bowl, whisk together flour, baking soda, and salt until evenly distributed.

Gradually pour dry ingredients into wet mixture, stirring gently until a soft dough forms. Do not overmix.

Scoop out approximately 2 tablespoons of dough for each cookie and roll into balls. Place on prepared baking sheets, leaving 2 inches of space between each ball.

Drain pineapple rings thoroughly and pat completely dry with paper towels to remove excess moisture.

Press one pineapple ring gently into the top of each dough ball, flattening slightly. You can cut rings in half if desired.

Sprinkle the additional sugar generously over the pineapple on each cookie to create caramelization during baking.

Bake for 11 to 13 minutes until edges are golden brown and centers look set. Don't overbake.

Let cookies cool on baking sheet for 5 minutes, then transfer to wire rack to cool completely before storing.