0. Let's start with the base: place the flour, cocoa, butter, and powdered sugar in a stand mixer and mix on medium speed with the paddle attachment for a few minutes, until the mixture resembles sand. Then, add the eggs and mix until it becomes firm and forms a dough. If you don't have a stand mixer, you can repeat the same process by hand.

1. Roll out the dough thinly between two sheets of parchment paper, making sure it's as evenly spread as possible, otherwise the finished tart will have varying thicknesses. Cut out the dough using a baking ring (silicone ones are fine), which will serve as the base of the tart. If you're making individual portions, cut out the base using the same individual portion molds. From the same rolled out dough, cut strips about 2 centimeters wide. This will allow us to have predefined shapes that can be easily removed from the dough once it has set. Important: the base and the strips should not be removed at this point, but simply "cut."

2. Place the dough in the refrigerator between the two sheets of baking paper for 2 hours, so that it firmes up before baking.

3. Once the dough has rested, separate the base and edges (the strips) and assemble them on the baking mold (ring or single portions), removing the excess dough from the edges.

4. Bake in a preheated oven at 170° for 25 minutes.

5. Once the crust is cooked, let it cool and fill with jam. Let it rest in the refrigerator.

6. Meanwhile, prepare the ganache. Place the cream in a saucepan and bring to a boil. As soon as it begins to boil, turn off the heat and add the chocolate. Stir with a whisk until the chocolate is completely melted and well combined. Pour the ganache over the jam to seal the tart. Transfer to the refrigerator and let the ganache harden.

7. We'll use the remaining ganache for the garnish. Using an electric mixer, whip the mixture until it reaches a frothy and stiff consistency. Transfer to a piping bag with a long nozzle and refrigerate for 30 minutes. Once firm, decorate the unwhipped ganache as desired (it should be very firm and solid).