Line two large baking sheets with parchment paper. Arrange the Ritz crackers in a single layer, leaving a little space between each cracker.

In a medium heavy-bottomed saucepan, combine the butter, brown sugar, and sweetened condensed milk.

Place the saucepan over medium-low heat and cook, stirring constantly with a silicone spatula, until the butter has melted and the mixture is smooth.

Continue cooking for approximately 8–10 minutes, stirring constantly and scraping the bottom and sides of the pan, until the caramel becomes noticeably thicker and turns a deeper golden color. Adjust the heat as needed to prevent scorching.

Reduce the heat to low and stir in the milk.

Add the chopped roasted peanuts and continue cooking for another 2–3 minutes, stirring frequently, until the mixture is thick enough to mound on a spoon rather than running off immediately.

Remove the saucepan from the heat. Working while the caramel is still warm and spoonable, place approximately 1 tablespoon of the caramel peanut mixture onto each Ritz cracker.

Gently spread the caramel toward the edges of the crackers, leaving a small border to help keep the topping in place.

Allow the cookies to cool completely at room temperature. If the caramel is still very soft, refrigerate the cookies for 20–30 minutes to help firm them before dipping. The topping should remain pleasantly chewy rather than becoming hard candy.

Place the milk chocolate melting wafers in a microwave-safe bowl. Microwave according to the package directions, stirring between short intervals until completely melted and smooth.

Drizzle the chocolate over the candies.

Allow the chocolate to set completely at cool room temperature, or refrigerate briefly until firm.

Once the chocolate has hardened, transfer the cookies to an airtight container.