Take everything you love about morning buns and hot chocolate then put them together to make these Hot Cocoa Buns. The soft dough is spread with a buttery chocolate filling and finely chopped dark chocolate that gets all melty and delicious in the oven. For the frosting, I used a shortcut by melting butter and mini marshmallows together before mixing with icing sugar and cocoa powder. The end result is sweet and chocolatey with a distinguishable, slightly chewy marshmallow texture.
If you dream of warm, gooey buns while still dressed in jammies, make the buns through shaping and putting them in their pan, cover then refrigerate overnight. Come morning, allow buns to come to room temperature, 60 to 90 minutes, then bake!
Chocolate Marshmallow Frosting
For the sweet dough, heat milk to 100-110°F, or hot to the touch. Stir in the yeast and 1 tablespoon sugar. Set aside until foamy, 5-10 minutes.
In the bowl of a stand mixer, stir together the remaining sugar, flour and salt. When the yeast mixture is ready, pour it into the dry ingredients followed by the egg and egg yolk. Stir with a wooden spoon or rubber spatula until combined and shaggy.
Begin mixing the dough with a dough hook on low speed until it comes together, 1-2 minutes. While the dough is mixing, add in the softened butter, a couple teaspoons at a time. Continue to knead the dough until all of the butter is incorporated. Increase the speed to medium-low and knead until the dough is smooth and elastic.
Tip the dough into a lightly greased bowl, cover and let rise until doubled in size, 90-120 minutes.
While the dough proofs, make the filling. Mix together the softened butter, brown sugar and cocoa powder to make a paste. Set aside.
Once the dough has proofed, punch it down to deflate. Turn the dough out onto a lightly floured surface and roll it out to a large rectangle, about 18×12 inches. Dollop the chocolate filling on top and spread it out evenly with an offset spatula. Sprinkle the chopped chocolate all over the filling.
Starting at the long side of the rectangle, roll up the dough into a log.
Slice the log into 12 equal pieces. Arrange the buns in a greased 9×13 inch baking pan. Cover and allow to rise until puffy, about 45 minutes. If poked with a finger, the dough should hold the indentation then slowly puff back out.
Meanwhile, preheat the oven to 350°F.
Bake the buns for 25-30 minutes, or until lightly browned on the outside with an internal temperature of 190°F. Remove from the oven and place on a wire rack to slightly cool as you make the frosting.
To make the frosting, in a saucepan over medium heat, cook the butter and water until the butter is melted. Stir in the marshmallows and cook until nearly melted.
Remove from the heat and whisk in the icing sugar until smooth. Add the cocoa powder and mix to combine.
Immediately spread the frosting over the buns. The frosting will set as it cools.
To finish, top with extra mini marshmallows and dust with cocoa powder. Hot Cocoa Buns are best served the same day as made. Store leftovers overnight in the refrigerator. A quick blast in the microwave for 10 to 20 seconds will warm and soften them right up.