For the Cupcakes:
1 1/2 cups (7 1/2 ounces) all-purpose flour
1/2 cup (1 1/2 ounces) cocoa powder
1 1/4 teaspoon baking soda
1/2 teaspoon salt
1 cup (7 ounces) granulated sugar
1/4 cup (1 3/4 ounces) packed light brown sugar
1 cup buttermilk
2/3 cup vegetable oil
2 large eggs
1 teaspoon pure vanilla extract
For the Green Ganache:
4 ounces white chocolate, finely chopped
3 tablespoons heavy cream
A few drops green food coloring
For the Chili Ganache Spiders:
10 ounces bittersweet chocolate, finely chopped
8 ounces heavy cream
1/2 teaspoon chili flakes (optional)
1 cup chocolate sprinkles
Licorice or sour candy strings
Sour candy for the eyes
Slivered almonds for the fangs
Procedures:
For the Cupcakes: Adjust oven rack to middle position and preheat oven to 350°F. Line standard muffin tin with cupcake liners. In medium bowl, whisk flour, cocoa, baking soda, and salt to combine; set aside. In large bowl, whisk sugar, brown sugar, buttermilk, oil, eggs, and vanilla to combine.
Whisk dry ingredients into we until batter is smooth. Fill cupcake cups 3/4 full and bake until firm to the touch and a cake tester or toothpick inserted into center comes out clean, about 19 minutes. Let cupcakes cool in pan for 5 minutes, then transfer to wire rack to cool completely before frosting.
For the Green Ganache: Heat white chocolate and cream in medium bowl in microwave or over pan of barely simmering water, stirring, until mixture is melted and smooth. Chill until firm enough to frost, about 30 minutes, Stir in green coloring to desired shade.
For the Chili Ganache: Heat bittersweet chocolate, cream, and chili flakes (if using), stirring, until mixture is melted and smooth. Adjust to taste with more chili if desired. Chill until firm enough to scoop, about 1 hour. Fill pastry bag fitted with large plain tip with ganache and pipe 12 round balls (1 per cupcake). Chill until just firm enough to handle, about 30 minutes.
Assemble Cupcakes: Frost cupcakes with green ganache. Roll chili ganache balls in sprinkles and place on cupcakes. Cut legs out of licorice sticks and stick into spider. Secure the eyes with dabs of extra chocolate ganache. Stick almond fangs into mouth. Serve.
Source: http://www.seriouseats.com/recipes/2012/10/chocolate-spider-cupcakes-recipe.html