Preheat oven to 375°F. Line a baking sheet with parchment paper.

Whisk together the flour, baking soda, and baking powder in a medium bowl. Set aside.

In a large bowl, beat the softened butter, peanut butter, granulated sugar, and brown sugar until smooth and creamy.

Add the egg and vanilla and beat until combined.

Add the dry ingredients and mix on low just until the dough comes together. If the dough is too sticky to roll, cover and chill for about 30 minutes.

Place the sugar for rolling in a small bowl. Scoop the dough by tablespoonfuls, roll into balls, then coat each ball in sugar.

Place the dough balls on the prepared baking sheet and lightly flatten each one with your hand.

Bake for 8–10 minutes, until the bottoms are lightly golden and the tops are still slightly soft.

Immediately press one mini Reese’s cup upside down into the center of each warm cookie.

Let the cookies cool on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely.

Melt the chocolate chips in a microwave-safe piping bag at 50% power, kneading between short intervals until smooth.

Pipe four chocolate legs on each side of the Reese’s cup.

Use a small dab of melted chocolate to attach two candy eyes to each spider.

Let the chocolate harden completely before serving or storing.