Combine softened butter and both sugars in a large bowl and beat on high for 2-3 minutes until smooth and creamy. Scrape the sides occasionally to ensure all butter and sugar are incorporated.

While butter and sugar are being beaten, combine flour, cocoa powder, baking powder, and salt in a medium bowl and set aside.

When the butter/sugar mixture is smooth and creamy, add the egg and the vanilla and beat on high until fully incorporated. Again, scrape the sides and the bottom and beat again to ensure all ingredients are combined.

Add the dry ingredients to the butter mixture and mix on low until just combined. Don't overmix.

Divide the dough between two pieces of parchment paper that have been dusted with cocoa powder. Sprinkle the dough with more cocoa powder, place another sheet of parchment paper over each dough ball and flatten slightly with your hand. Using a rolling pin, flatten the dough further to a uniform 1/4 inch thickness.

Transfer the dough, sandwiched between the sheets of parchment paper to the refrigerator where it can lay flat. I found it easiest to lay them on a small baking sheet. You can stack one sandwiched piece of dough on top of the other.

Let the dough chill for at least 2 hours.

Preheat oven to 350°F

Line cookie sheets with parchment paper or silicon baking mats.

Take one flattened piece of dough from the refrigerator and cut squares with a cookie cutter. Place dough squares onto prepared cookie sheets, one inch apart. Work quickly, as the dough will soften quickly. Gather the dough scraps, flatten them between two sheets of parchment, and roll them to 1/4" thick. Put the flattened scraps back in the refrigerator. Continue to repeat the process until all the dough has been cut.

When you have a cookie sheet filled, pop it back in the refrigerator for 15-20 minutes.

After 20 minutes, place the cookie sheets in the oven and bake for 10-11 minutes.

Allow the cookies to cool on the baking sheets for 5 minutes before transferring them to a wire rack for further cooking.

Pour the heavy cream into a 1-cup microwavable bowl.

Place the chocolate chips into another 1-cup or larger heatproof bowl and set aside.

Microwave the cream for 20-30 seconds, watching closely. You want to start seeing bubbles but don't want it to boil over.

Pour the hot cream over the chocolate chips, but don't stir! In fact, resist the urge to fiddle with the bowl at all for 3 minutes.

Then, with a spatula or a whisk, start stirring from the center of the bowl, slowly moving out to the edge of the bowl. Whisk in one direction until the cream and chocolate are combined, and the mixture is thickened.

Let cool to room temperature before using it to fill the cookies.

Once cool, tuck the ganache into a piping bag fitted with a #10 round tip.

Add all ingredients to the bowl of a stand mixer fitted with a whisk attachment.

Beat at low speed for 7-10 minutes until peaks form.

Check your icing; If it is too stiff, add water 1/2 teaspoon at a time. If it is too thin, add powdered sugar 1 tablespoon at a time. You want the consistency of toothpaste, maybe a touch thicker even.

Once fully cooled, pipe the ganache around all four edges of the back side of half of the cookies. I used a Round #10 tip. Feel free to use a fluted tip for a ruffly filling.

Place the jelly in a small, microwavable bowl and zap for about 10 seconds. If it isn't melted, zap it for another 5-7 minutes. You want it slightly runny.

Put small dollops of melted jelly in the center of the ganache squares on half of the cookies.Top with the other halves of the cookies.

Draw 'ribbons' and 'bows' on the cookies, using a size #3 piping tip.

Let the frosting dry completely before storing your cookies.