Begin by microwaving ½ cup of peanut butter for about 30 seconds or until it's slightly warm and easier to stir. In a bowl, mix the melted peanut butter with 1 cup of sifted powdered sugar and ½ teaspoon of ground cinnamon until smooth. Once combined, scoop out dollops of the filling onto wax paper and freeze for 1 hour to firm up.

In a separate mixing bowl, sift together 1 ½ cups of all-purpose flour, ½ cup of Dutch process cocoa powder, 1 teaspoon of baking soda, and a pinch of salt. This step is crucial for ensuring there are no lumps and your dry ingredients are well blended. Set this mixture aside as you prepare the cookie dough.

In another large bowl, whisk together ½ cup of melted unsalted butter, ½ cup of packed brown sugar, ½ cup of granulated sugar, 1 teaspoon of pure vanilla extract, and 2 large eggs until the mixture is well combined and creamy. Gradually add the dry ingredients from Step 2 to this wet mixture, stirring until just combined. Fold in 1 cup of semi-sweet chocolate chips.

Allow the cookie dough to rest for about 10 minutes at room temperature. Using a cookie scoop, portion out the dough into balls. Create a pocket in each ball with your thumb, insert a frozen dollop of peanut butter filling, and encase it with more dough.

Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper. Place the filled cookie dough balls on the sheets, spacing them a couple of inches apart. Bake for 13-15 minutes, or until the edges are set but the centers look soft. Let the cookies cool on the sheets for 5 minutes before transferring them to a cooling rack.