Erin Clarkson's One Bowl Chocolate Cupcakes with Sour Cream Ganache

Super easy, super delicious these one-bowl chocolate cupcakes with dark chocolate sour cream ganache frosting from Cloudy Kitchen's Erin Clarkson are a real crowd pleaser and perfect for SPCA Cupcake Day. A little note from Erin "The cupcakes themselves are crazy easy to make - everything comes together in the one-bowl. The ganache is something that I am super excited to share with you. I was so excited that it worked when I tried it a few weeks ago, and I think that it is going to be a game changer when it comes to a pipable ganache. I used a dark chocolate in this ganache, but I think that it would be so, so delicious with a milk chocolate too, which would really bring out the flavour of the sour cream."

A few wee tips:

• The Sour Cream ganache takes a few hours to firm up to a piping consistency, so make sure that you account for this. I like to make it first before I preheat the oven for the cupcakes, so there is enough time for it to firm up.
• I used an ateco #826 piping tip (A Large Star tip like a Wilton 1M) for this because the ganache, while perfect for piping onto these cupcakes, can be a touch less forgiving than a buttercream for piping, so I used a tip that is really easy to make ruffles with - you just hold the tip above the cupcake and it does most of the work for you! If you are using another tip just keep this in mind, as the ganache doesn’t behave just like a buttercream does.
• This recipe also bakes into a 9” square sheet cake - it takes about 35 minutes to bake.

NB: If you're not already following Erin's incredible recipe inspiration @cloudykitchen we highly recommend you do, but prepare to be very tempted and inspired. 

INGREDIENTS

250g plain flour
250g white sugar
80g dutch process cocoa
2 tsp instant coffee powder
½ tsp salt
1 tsp baking soda
1 ½ tsp baking powder
2 eggs
1 egg yolk
1 tsp vanilla bean paste or vanilla extract 
120g neutral oil
220g whole milk, at room temperature
200g boiling water

Dark Chocolate Sour Cream Ganache Frosting
560g good quality dark chocolate (Erin used 70%), chopped
500g full-fat sour cream, at room temperature
Crispy pearls or flaky sea salt to finish, optional

METHOD

Preheat the oven to 180°c. Line a muffin pan with cupcake liners (This recipe made 14 to 16 cupcakes so you may need two pans, or you can bake them separately).
In a large bowl, whisk together the flour, sugar, cocoa, espresso powder, salt, baking soda, and baking powder. Add the eggs, yolk, vanilla, oil, and milk, and mix to combine well. Add the boiling water and whisk until incorporated.
Scoop about ¼ cup plus 2 Tbsp of batter into each liner using a cookie scoop (I have a ¼ cup scoop and a 2 Tbsp, or you could use a quarter cup measure).
Bake the cupcakes for 19 to 20 minutes, or until they spring back when touched, or a toothpick inserted into the cupcake comes out clean.
Cool on a wire rack.

Frosting

Place the sour cream and chopped chocolate into a heat proof bowl, and mix to combine.
Microwave for 30 second intervals, stirring well between each interval (it will likely take a minute, but watch carefully). Once the chocolate is melted, switch to a whisk and whisk the ganache until it is well combined and shiny. Scrape down the edges of the bowl with a spatula. Press a piece of plastic wrap over the surface of the ganache, and leave to sit at room temperature for 2-3 hours, or until it has thickened and is a pipeable consistency.

Assembly

Transfer the ganache to a piping bag fitted with a large open star tip. Pipe ruffled piping onto the cupcake, by holding the piping tip directly above the cupcake, and piping a mound of ganache. Repeat with the remaining cupcakes. Finish with sprinkles, crispy pearls, or flaky sea salt, as desired.