RECIPE PREP: Preheat oven to 375°F. Line 2 trays with parchment paper and set them aside. Unwrap the truffles.

1. Make the cookie dough. In the bowl of stand mixer, cream together the butter, peanut butter, granulated sugar and light brown sugar until light and fluffy. Add egg and vanilla extract. Beat until well blended. Add in flour, baking soda, baking powder and salt. Blend just until incorporated. Don’t overmix, or the cookies will be heavy and dense instead of light and tender.
2. Scoop the cookie dough. Use a 1-inch cookie scoop to drop balls of cookie dough onto the prepared baking trays, placing them 2-inches apart. Dust the top of the cookies with a pinch of granulated sugar. Gently and lightly flatten them out a bit with a pestle or your thumb to help them spread out in the oven.
3. Bake the cookies for 8 minutes, or until the edges are light golden blonde. The centers will be soft – which is perfect. Immediately create a shallow depression in the middle of each warm cookie with your thumb.
4. Let the cookies cool completely. Then place the tray of cookies into the fridge for 10 to 15 minutes to make double sure they’re cool all the way through. If we add truffles to slightly-warm cookies, the chocolate will melt due to residual heat.
5. Melt the dark chocolate morsels: Add chocolate morsels to a microwave-safe bowl. Microwave 30 seconds, then stir. Microwave 30 seconds more, and stir again. Then microwave in 15-second intervals, stirring between sessions, until chocolate is melted and smooth. Transfer chocolate to a piping bag with a small round metal tip.
6. Assemble the spider cookies. Use the melted chocolate to adhere the truffles to the cookies. Each truffle has a round indent at the bottom. Position the truffle on each cookie with that indent facing forward and slightly downward as the “mouth.” Use melted chocolate to stick candy eyes onto the truffles. Pipe 8 legs onto each peanut butter spider cookie (4 on each side of the body). Let chocolate set before serving.