Adjust oven rack to the middle position and preheat the oven to 325 F. Line a 12-cup cupcake tin with liners and set aside.

Whisk together flour, baking soda, and salt in a medium bowl then set aside. In a large bowl, add cocoa powder and chocolate chips. Add the boiling water, and let it sit a minute or two to melt the chocolate. Whisk until smooth. Add sugar, sour cream, oil, eggs, and vanilla extract and whisk until combined and smooth. Add dry ingredients and whisk until just combined and no flour lumps remain. Evenly distribute the batter into the cupcake liners and bake for 18-20 minutes, or until a toothpick inserted into the middle of one of the cupcakes comes out with a few dry crumbs. Remove from the oven and allow to cool in the tin for about five minutes. Then remove cupcakes from the tin and let cool completely on a cooling rack. 

In a small bowl, mix together the seedless raspberry puree and sugar. Stir until sugar is dissolved, then set aside. 

Place water in a small bowl, then sprinkle gelatin over the top. Let bloom for five minutes. Microwave for 30 seconds (or until the gelatin is just bubbling). Pour the mixture into a medium-sized bowl and add the butter, vanilla, and salt. Stir until better is completely melted, then add the sweetened raspberry puree. With a whisk, stir in the marshmallow fluff and mix until it is incorporated. Cover the bowl with plastic wrap and place in the fridge for 30 minutes. 

Remove filling mixture from fridge. Set aside 1/3 cup of the filling in a small ziplock bag or a piping bag fitted with a small, plain tip. (This is for the swirls on top. If you use a ziplock bag, you can just cut a very small hole in one corner to pipe the swirls.)

Take a cupcake and make a cone-sized cut out of the middle. Fill the hole with one tablespoon of the filling mixture. Replace the top back on the cupcake. If the hole is really full, you can cut the bottom off the cone before you place it back on top. Repeat with each cupcake. 

To make the chocolate glaze, combine chocolate chips and butter in a small bowl. Microwave in 30-second increments until chocolate is mostly melted, stirring after each 30 seconds (this will take less than a minute). Stir well until chocolate chips are melted and mixture is smooth. 

Using an offset spatula, scoop 2 teaspoons of the glaze on the top of each cupcake and spread it around until it's nice and even. Let the cupcakes set up for a minute or two. Use any extra glaze to smooth out any edges on the cupcakes. Using the filling set aside in the bag, pipe curlicues (or heart-shaped curlicues, as I have) on the top of each cupcake. Let set up before eating. Cupcakes are best eaten within a day or two. Enjoy!