Preheat the oven to 350 degrees and line a cupcake pan with four paper liners.
In a mixing bowl, whisk together the flour, dark cocoa powder, sugar, baking soda, and salt.
Add the egg, milk, vegetable oil, and vanilla extract to the dry ingredients and stir until combined.
Pour in the hot water and mix until the batter becomes smooth and thin.
Divide the batter evenly among the four liners and bake for 18 to 20 minutes until a toothpick comes out clean.
Let the cupcakes cool completely on a wire rack.
Use a small knife to cut a shallow cone from the center of each cupcake and fill the hole with raspberry preserves.
In a small saucepan, heat the heavy cream until it just begins to steam, then pour it over the dark chocolate chips in a bowl.
Stir the cream and chocolate until the ganache is glossy and fully melted.
Spoon the ganache over each filled cupcake and let it set for a few minutes before serving.