Ghostbuster Cupcake Recipe

Here are the ingredients that you need to compile to make these cupcakes:

Lime Slimer Cupcakes

  • 6 Tbsp (3/4 of a stick) unsalted butter, room temperature (85 grams)
  • 3/4 cup granulated sugar (150 grams)
  • 1/3 cup pasteurized egg whites or 3 egg whites (90 grams)
  • 1/3 cup sour cream (80 grams)
  • 1/3 cup whole milk (80 grams)
  • 1/4 cup lime juice (60 grams)
  • 1 tsp vanilla extract (4 grams)
  • 2 tsp lime zest (4 grams)
  • green gel food coloring
  • 1 1/4 cups all-purpose flour (163 grams)
  • 2 tsp baking powder (8 grams)
  • 1/4 tsp salt (2 grams)

Lime Curd

  • 3 large eggs (168 grams)
  • 3/4 cup granulated sugar (150 grams)
  • 1/4 tsp salt (2 grams)
  • 1/2 cup fresh lime juice (120 grams)
  • 1 Tbsp lime zest (6 grams)
  • 6 Tbsp (3/4 stick) unsalted butter (85 grams)
  • green gel food coloring

Lime Buttercream Frosting:

  • 1 cup unsalted butter, room temp (226 grams)
  • 1 tsp vanilla extract (4 grams)
  • 1/2 tsp salt (3 grams)
  • 2 Tbsp lime juice (12 grams)
  • 1 tsp lime zest ( grams)
  • 3 1/2 cups powdered sugar (438 grams)
  • green gel food coloring


Here are the instructions that you need to follow to complete this recipe:

Lime Slimer Cupcakes

  1. Preheat the oven to 350°F and line a cupcake pan. Set aside.
  2. In a large bowl or the bowl of a stand mixer, cream together 6 Tbsp butter and 3/4 cup sugar until the mixture becomes lighter in color (1-2 minutes).
  3. Mix in 3 egg whites on a medium speed, scraping down the sides and bottom of the bowl as needed with a rubber spatula.
  4. Mix in 1/3 cup sour cream, 1/3 cup whole milk, 1/4 cup lime juice, 1 tsp vanilla, 2 tsp lime zest and a squirt of gel food coloring on a medium speed until combined.
  5. In a separate bowl, whisk together 1 1/4 cups flour, 2 tsp baking powder and 1/4 tsp salt.
  6. Mix in the dry ingredients in two additions, mixing on a low speed until just combined. Be careful not to overmix the batter!
  7. Fill the cupcake liners 3/4 full and bake for 15-17 minutes or until a toothpick comes out with a few moist crumbs.
  8. Remove cupcakes from oven and let them to cool for 2-3 minutes in the pan, then place them on a wire rack to finish cooling.

Lime Curd “Slime” Filling

  1. While the cupcakes bake and cool, make the lime curd filling.
  2. Whisk together 3 large eggs, 3/4 cup sugar, 1/4 tsp salt, 1/2 cup lime juice and 1 Tbsp lime zest in a medium saucepan until smooth.
  3. Heat over a medium low head for 10-15 minutes stirring constantly until the mixture thickens.
  4. Turn off the heat and stir in 6 Tbsp of butter and a squirt of green gel food coloring until smooth and evenly colored. Pour into a separate bowl to cool and set aside.

Lime Buttercream

  1. As the lime curd filling cools, make the lime buttercream.
  2. Beat 1 cup of room-temperature butter on a medium-high speed for 2 minutes with a whisk attachment until the butter becomes lighter in color.
  3. Mix in 1 tsp vanilla extract, 1/2 tsp salt, 2 Tbsp lime juice and 1 tsp lime zest on a low speed.
  4. Slowly mix in 3 1/2 cups of powdered sugar, 1 cup at a time on a low speed.
  5. Mix on low for a couple minutes until the ingredients are fully incorporated.
  6. If the frosting is too thick, add in additional lime juice (1 Tablespoon at a time). If the frosting is too thin, add in more powdered sugar (1/4 cup at a time).

Assembling These Slimer Cupcakes

  1. Use a small knife or 1 inch circle cutter to remove the center from each cooled cupcake.
  2. Fill each cupcake with a generous spoonful of lime curd.
  3. Pipe a large swirl of lime buttercream on top of each cupcake. Chill the cupcakes in the fridge for 10 minutes to help the frosting firm up.
  4. While the cupcakes chill use black, white and red fondant to make slimer’s mouth and eyes.
  5. Remove the cupcakes from the fridge and add a Slimer face to each cupcake, then enjoy!