I found this recipe from http://www.chewoutloud.com/2014/09/08/hostess-cupcakes/
These taste so much like Hostess Cupcakes (without the fake flavor!)
I got 15 cupcakes out of one batch of these.
1 cup flour
1/2 tsp baking soda
1/4 tsp salt
1/2 cup boiling water
1/3 cup cocoa
1/3 cup mini chocolate chips
1 Tablespoon instant coffee powder
3/4 cup sugar
1/2 cup sour cream
1/2 cup vegetable oil
2 large eggs
1 tsp vanilla
3 Tablespoons water
3/4 teaspoon unflavored gelatin (I used Knox)
4 Tablespoons butter
1 tsp vanilla
pinch of salt
1 1/4 cup marshmallow fluff
1/2 cup chocolate chips
3 Tablespoons butter
Preheat the oven to 325 degrees. Line 15 muffin cups with liners.
Fold in the dry ingredients. Be careful to not over mix.
Bake for about 18 minutes. (The rack in the oven should be placed on the lower middle level.) Cool cupcakes for about 5 minutes and transfer to a wire rack to complete cooling.
Combine 3 Tablespoons of water with 3/4 tsp of gelatin in a microwavable bowl. Let it sit for about 1 minute so the gelatin can soak up some of the water. Then microwave the mixture for 10 seconds at a time, until the mixture starts bubbling around the edges and the gelatin is dissolved. (It took mine 50 seconds).
Stir in 4 Tablespoons butter, 1 tsp vanilla, and a pinch of salt. Let the mixture cool for a few minutes. Whisk in 1 1/4 cups marshmallow fluff until it is smooth. Chill for about 30 minutes or until set. Put about 1/2 cup of the mixture in a plastic ziploc bag. Cut the tip off a corner of the bag. Set aside the remaining filling to be used to fill the cupcakes.
For the glaze, microwave the 1/2 cup chocolate chips and 3 Tablespoons butter in a bowl for 30 seconds at a time. Stir until smooth.
Cut a triangle shape piece out of the center of the cooled cupcakes. Fill the center with the remaining marshmallow filling. I used a decorating tool to fill mine. A plastic bag with the tip cut off would work for this step as well though.
Trim the excess pieces of cake you cut out so just the top is left. Place the top back on top of the filling.
Put the melted chocolate glaze on top of the cupcakes.
Then use the filling already in the plastic bag to create a decoration on top. We turned ours into footballs. They don't have to be refrigerated, but taste best chilled.
I am going to freeze some for a quick treat or for the kids' lunches.