Preheat your oven to 350°F (175°C). Grease a 9-inch round cake pan with butter and set it aside.
In a large mixing bowl, combine the melted butter and cocoa powder. Whisk until well blended, forming a thick paste. Gradually add the sugar, mixing until combined.
Add the eggs one at a time, whisking well after each addition. Stir in the tablespoon of pure vanilla extract until fully incorporated.
Sift together the all-purpose flour and kosher salt. Gradually add the flour mixture to the chocolate mixture, stirring gently until just combined. Be careful not to overmix.
Gently fold in the chopped Reese’s Cups, ensuring they are evenly distributed throughout the batter.
Pour the batter into the prepared cake pan and smooth the top with a spatula. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.
Once baked, remove the torte from the oven and let it cool in the pan for 10 minutes. Then, transfer it to a wire rack to cool completely.
While the torte cools, prepare the ganache. In a microwave-safe bowl, combine the 3 tablespoons of peanut butter, confectioners' sugar, and 1 teaspoon of vanilla extract. Heat the heavy cream in the microwave until it begins to simmer, then pour it over the peanut butter mixture. Stir until smooth and creamy. If the ganache is too thick, add more heavy cream until you reach the desired consistency.
Once the torte is completely cooled, pour the peanut butter ganache over the top, allowing it to drip down the sides. For an extra touch, sprinkle some additional chopped Reese’s Cups on top for decoration.
Allow the ganache to set slightly before slicing the torte into wedges. Serve as is or with a dollop of whipped cream for an added indulgence.