CNS Stimulating Mocha Cupcakes

Ivka, one of my lab friends, celebrated her birthday yesterday. She, as well as the rest of the serious scientists, cannot imagine a day without coffee. It is understandable, considering the hours spent in dark rooms, sterile environment without windows, and late afternoon and evening shifts... From all the different flavours of cupcakes, Ivka likes the mocha ones with espresso mascarpone frosting the most, and it was therefore the obvious choice for our little "lab-rat" celebration... 

C2H10N4O2, or caffeine, is a xanthine alkaloid compound found in the leaves and beans of coffee plant. It acts as a CNS stimulant in humans and, as such, it has the power to temporarily ward off drowsiness and restore alertness. Caffeine has several other names which are often mentioned when talking about its different sources. These include guaranine, mateine, or theine found in guarana berries, verba mate, and tea, respectively. From the evolutionary perspective, caffeine, commonly found in over 60 plant species worldwide, is believed to have a protective role, as it acts as a natural pesticide which paralyses and kills various insects.

Apart from caffeine, coffee also contains trigonelline, a bitter alkaloid which has a significant role in the development of flavours and aromas during roasting. During the roasting process, trigonelline decomposes and gives rise to a large class of aromatic compounds (pyridines). These are responsible for producing the sweet/caramel/earthy-like aromas.

The coffee aroma is perceived by two different mechanisms. We can sense the scent nasally via smelling the coffee through the nose, or retronasally, when we swallow the coffee or when it is present in our mouth and the volatile aromatic compounds drift upward into the nasal passage.

Mocha Cupcakes with Espresso Mascarpone and Dark Chocolate Frosting - Notice the beautiful new cases! 

Ingredients (makes for about 12 cupcakes)

     Cupcakes
2/3 cup plain flour
1/2 cup brown sugar
1/4 cup cocoa powder
1/4 cup butter
1/4 cup whole milk
1/4 cup strong black coffee
0.5 tbsp. baking powder
0.5 tsp. vanilla extract* (not the Dr.Oetker clear essence!)
0.25 tsp. salt
0.25 tsp. baking soda
1 large egg
*the only good vanilla extract I discovered in CZ/SK so far is the one from Marks and Spencers, in the UK I like the one from Dr.Oetker (brownish and thick, available with, or without the vanilla seeds)

     Espresso Mascarpone Frosting
200 g mascarpone cheese
6-8 tbsp. powdered sugar
2-3 tsp. instant coffee powder
(1-2 tbsp. heavy cream if the frosting turns out too thick)

     Dark Chocolate Frosting
40 g quality dark chocolate (melted)
2/3 cup cocoa powder
1/2 cup butter (softened)
1/3 cup heavy cream
4-6 tbsp. powdered sugar

Directions
      Cupcakes
1. Preheat oven to 180°C
2. Whisk together sugar and softened butter
3. Add the egg and whisk to blend
4. Add tepid coffee, milk, and vanilla extract and mix thoroughly
5. Mix the dry ingredients and slowly add the dry mixture to the wet one, whisk thoroughly until smooth
6. Line a cupcake/muffin pan with cupcake cases and fill each one a about 2/3 full
8. Bake for about 20 minutes (toothpick inserted in the centre should come out mostly clean)

     Espresso Mascarpone Frosting
1. Whisk together mascarpone with the instant coffee powder
2. Add sugar (less if you like your coffee more bitter) and whisk to blend
3. If too thick, whisk in some cream

     Dark Chocolate Frosting
1. Whisk together the softened butter and cocoa powder
2. Add melted chocolate and cream and mix thoroughly
3. Stir in sugar and beat until smooth