New Year's Chocolate Muffins

Back from my weird Christmas holidays and looking forward to the new year, I'm gonna share what it is going to be the last recipe of 2010.
This has been the year of experimenting and learning lots of new recipes techniques and I'm even more in love with this sweet and always tempting (and addictive) world of bakery.
The following recipe is a New Year's customized version of one of my favorites chocolate muffins. I put over the top two different decorations: powdered gold food colouring and chantilly cream.

Hope you all have an awesome New Year's Eve! May 2011 be the best year of your lives! I'll definitely work hard for making this new year unforgettable. :-)
New Year's Chocolate Muffins

100g (3.38 fl oz) soft unsalted butter.
1/2 cup sugar.
1/2 cup packed brown sugar.
2 large eggs.
2/3 cup sour cream.
5 tbsp milk.
1 3/4 cup all-purpose flour.
1 tsp baking soda.
2 tbsp pure cocoa powder.
1 cup bittersweet chocolate chips.

Preheat oven to 190ºC (374ºF). Place 12 cupcake liners into muffin tins.

Beat well butter, sugar and brown sugar in a large bowl. Add in the eggs, the sour cream, the milk and keep beating until all ingredients are blended.

In another bowl stir together flour, baking soda and cococa powder; add it to the sweetened batter.
Fill the cupcake liners with the batter and bake for around 25 to 30 minutes.

Take out the pan from oven and let it set 10 minutes. Remove cupcakes from pan and let cool completely on wire racks.