Prepare Baking Sheets: Line two baking sheets with parchment paper or silicone mats and preheat your oven to 350°F (177°C).

Combine Dry Ingredients: Whisk together all-purpose flour, cocoa powder, baking powder, and salt in a large mixing bowl.

Cream Wet Ingredients: Beat softened butter, brown sugar, and granulated sugar until light and fluffy. Add egg yolk and vanilla extract, mixing until well combined.

Combine Mixtures: Gradually add the dry ingredients to the creamed mixture, mixing until just combined.

Scoop and Shape: Use a cookie scoop to portion out dough, rolling into 1-inch balls and placing them on the prepared baking sheets.

Create Wells: Press a measuring spoon into the center of each dough ball to create an indent and chill the dough for at least 1 hour.

Bake: Bake the cookies for 9-11 minutes until edges are firm and tops slightly set.

Reshape Wells: Quickly reshape the indentations with a measuring spoon if they puffed up during baking.

Prepare Caramel Filling: Combine chewy caramels and milk in a microwave-safe bowl and heat until smooth.

Fill Cookies: Pour the melted caramel mixture into the wells of each cookie.

Drizzle Chocolate: Melt semi-sweet chocolate and drizzle over each filled cookie.

Serve and Store: Allow cookies to cool until chocolate sets and store any leftovers in an airtight container.