Cosmic Cupcakes for Plutopalooza

I learned quite a few years ago to embrace my inner sci-fi/space geek. If you know me in real life, you’re already well aware of this. I’m a not-so-fat sarcastic Star Trek fan. I’m obsessed with MST3K. I remember seeing the movie SpaceCamp as a kid and I actually started working on a letter to NASA, asking if they’d ever consider really sending kids into space, in spite of the Challenger disaster. In reality, I just don’t have the STEM background that’s necessary to be an adult astronaut.

Even now, though, I’m fascinated by the idea of space travel and exploration, athough it’s unlikely I’ll see or experience either one during my lifetime. Jay’s interested in space exploration too, and for the past year, has been following the New Horizons space probe on its journey towards Pluto. We’ll see if it looks anything like this:

Pluto Landing (Voyage to the Planets and Beyond - 2004)

The probe will make its closest flyby tomorrow, the 14th, but since today’s Jay’s birthday, we decided to combine celebrations. And so, I made some Cosmic Cupcakes.

Cosmic Cupcakes

We were discussing Plutopalooza while in line at the grocery store one evening, and the bambino spied the Little Debbie display, which included Cosmic Cupcakes. He begged for a box and I told him I could make a homemade version. He thought that was amazing and asked if I would.

Cosmic Cupcakes

He then proclaimed them the best cupcakes I’ve made so far. I suppose they are, between the cake itself, with its sweet, fudgy chocolate flavor, to the ganache, as well as the creme filling:

Cosmic Cupcakes

And how can you not love a cupcake topped with sprinkles? Especially star-shaped sprinkles!

Yield: 12-18

Cosmic Cupcakes for Plutopalooza

Cosmic Cupcakes for Plutopalooza


For the Cupcakes:

  • 1/2 C (1 stick) unsalted butter, room temperature
  • 1 C sugar
  • 1 tsp. vanilla extract
  • 2 large eggs
  • 1 1/3 C all-purpose flour
  • 1/2 C unsweetened cocoa powder
  • 1 1/2 tsp. baking powder
  • 2/3 C milk

For the Creme Filling:

  • 1/2 C (1 stick) unsalted butter, room temperature
  • 1 7oz. container marshmallow creme

For the Ganache:

  • 1/2 C heavy cream
  • 8 oz. semi or bittersweet chocolate, chopped
  • Star sprinkles


Preheat the oven to 350 degrees F. Line 2 muffin tins with 18 paper liners, and set aside.

In a small mixing bowl, whisk together the flour, cocoa powder, and baking powder. Set aside.

In a large mixing bowl, beat the butter and sugar together until light and fluffy. Add the vanilla. Add the eggs one at a time, mixing well after each addition.

On low speed, alternately add the flour-cocoa mixture with the milk, beginning and ending with the flour.

Using a large (3-Tbsp) scoop, place the batter in the prepared muffin tins. Bake 22-25 minutes, or until a toothpick inserted in the center of several cupcakes comes out clean.

Cool 10 minutes in the pans, then remove and cool completely on wire racks.

While the cupcakes are baking, make the ganache. Place the chocolate in a heat-proof bowl, and bring the cream to a simmer (do not let it boil). Pour the cream over the chocolate, and allow to sit for 5 minutes. Stir or whisk until combined and smooth. Let cool at room temperature for 2-3 hours, stirring occasionally, until thick enough to spread.

While the cupcakes are cooling, combine the butter and the marshmallow creme. Whisk or mix with a hand mixer until combined. Place in a zip-top bag and chill in the refrigerator for 15-20 minutes.

To assemble the cupcakes, cut a portion out of the cooled cakes, using a cupcake corer. Cut the tip off the bag containing the butter-marshmallow creme, and pipe enough to fill the hole. Replace the cake "divet" cutting a portion off the bottom if necessary. Spread ganache over the top of the cupcakes and decorate with star sprinkles. If the ganache is still somewhat thin, refrigerate for 20-30 minutes to allow it to set up.

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Happy Birthday to Jay…And Happy Plutopalooza!