Cupcake of the Month - Chocolate Zucchini Cupcakes with Vanilla Swiss Buttercream

Don't let the zucchini in these cupcakes scare you. I guarantee, you and your kids will never believe there is any zucchini in them. These are so good, you'll be wanting to replace your favorite chocolate cake recipe with this one. These are just as delicious without the icing, and even better the day or two after you've baked them - moist, rich, chocolately, soo good!  Also be sure to try this recipe for the zucchini chocolate cake I made last year. It was really good too - and had a chocolate frosting that was to die for!

Chocolate Zucchini Cupcakes
adapted from King Arthur Flour

1/2 cup (1 stick or 4 ounces) butter at room temperature
1/2 cup vegetable oil
1 3/4 cups (12 1/4 ounces) granulated sugar
1 teaspoon vanilla
2 1/2 cups (10 1/2 ounces) King Arthur Unbleached All-Purpose Flour
3/4 cup (2 1/4 ounce) Dutch-process cocoa (I used Hershey's Special Dark here)
2 teaspoons espresso powder, optional but really helps to bring out the rich chocolate flavor
1 teaspoon baking soda
1/2 teaspoon baking powder
1/2 teaspoon salt
2 large eggs
1/2 cup (4 ounces) sour cream or yogurt
2 cups finely shredded zucchini (I use the small grater on the food processor for this job)
1/2 cup (3 ounces) chocolate chips

1. Preheat the oven to 325°F. Line the cupcake pans with paper liners (makes at least 24).
2. In a medium bowl, whisk together the flour, cocoa, espresso powder, baking soda, baking powder, and salt and set aside.
3. In a large mixing bowl, cream together the butter, oil, sugar, and vanilla.
4. Beat in the eggs.
5. Stir in the sour cream or yogurt alternately with the flour.
6. Then fold in the zucchini and chocolate chips.
7. Fill the cupcake liners 2/3 full. Bake for 20 to 25 minutes, till the top springs back lightly when touched, and a toothpick inserted in the top comes out clean. Cool in the pans on a wire rack. Frost with Vanilla Swiss Buttercream (recipe below) and garnish with real chocolate sprinkles.
Swiss Buttercream
from Smitten Kitchen

1 cup sugar
4 large egg whites
26 tablespoons butter, softened (3 sticks plus 2 tablespoons)
1 teaspoon vanilla extract

1. Whisk egg whites and sugar together in a big metal bowl over a pot of simmering water. Whisk occasionally until you can’t feel the sugar granules when you rub the mixture between your fingers.

2. Transfer mixture into the mixer and whip until it turns white and about doubles in size. (Here’s a tip: when you transfer to the mixer, make sure you wipe the condensation off the bottom of the bowl so that no water gets into the egg whites. This can keep them from whipping up properly.)

3. Add the vanilla.

4. Finally, add the butter a stick at a time and whip, whip, whip until it comes together. This may take as long as 15 minutes.

5. Transfer the icing to a piping bag (I used a large Ateco #828 tip) to pipe icing onto the cupcakes or spread icing on using a small offset spatula.