Orange Cupcakes with Chocolate Buttercream Frosting

So the other night, I was trying to come up with several new flavors for cupcakes.  I thought of pairing orange with chocolate since the two go so well together. In my opinion, they should win the best food couple ever. Luckily, I just bought a big bag of oranges when I went grocery shopping. And I also have tons of cocoa powder in my pantry. The recipe for the cake portion is basically the same as the one for my previous entry, except instead of adding cinnamon and brown sugar to the batter, I added the zest of two oranges. The texture of these cupcakes is perfect--nice and light, fluffy and moist, with a very nice orange flavor. Buttercream is also a very easy thing to make. Once you have the basic, crucial ingredients (butter and powdered sugar), you can basically add any flavoring to it to make your favorite flavor of frosting. This recipe makes 12 cupcakes. With that being said, here is the recipe:

For the batter:
1/2 c. softened butter (1 stick)
1 c. sugar
2 eggs
zest of 2 oranges
2 tsp vanilla
1 1/2 c. flour
1/2 tsp. baking powder
2/3 c. cold milk
Preheat oven to 350. In a mixer on medium speed, cream butter and sugar. Add eggs one at a time, beating after each addition. When the eggs are thoroughly mixed with the butter and sugar, mix in the vanilla. In  a separate bowl, combine dry ingredients and add to the butter mixture, a little bit at a time. Mix on medium speed as well. When the dry ingredients are well incorporated, add the milk and orange zest  to the mixing bowl and mix until well combined.  Spoon the batter equally into each paper muffin liner and bake for 18-24 minutes. I baked these for 21 minutes. After 21 minutes, poke a small hole into one of the cakes with a toothpick. If it comes out clean, the cupcakes are done. Set the cakes aside to cool.

Now for the buttercream! You will need:
2 T cocoa powder, unsweetened
1/4 c. hot milk
1/2 c. butter, softened ( 1 stick)
2 1/2 c. powdered sugar

Mix the cocoa powder and the hot milk in a mug and set aside to let it cool completely. In a mixing bowl, combine the butter and cocoa/milk mixture, and beat at medium speed. Gradually add the powdered sugar and continue to mix at medium speed until smooth and fluffy. If your frosting seems to be on the thin side, add a little more powdered sugar to the mix. The cornstarch present in the powdered sugar acts as a thickener. When the frosting is at your desired consistency and the cupcakes are cool, spoon it into a ziploc bag and cut a small hole in the corner of the bag. Pipe the frosting onto each cupcake, then eat and enjoy your creation!