Step 1

Preheat oven to 350F.

Step 2

In the bowl of a standing mixer, cream together butter and and brown sugar until smooth. Add egg and beat until mixture is fully-incorporated and fluffy.

Step 3

In a bowl, whisk together flour, cocoa, baking soda, and salt. Set aside.

Step 4

In a large measuring cup, combine milk and sour cream. Set aside.

Step 5

Alternating between the dry and wet ingredients, add them to the butter-sugar mixture in two parts.

Step 6

Using an ice cream scoop, scoop out cake batter into the cavities of the lined cupcake pan.

Step 7

Bake for 20 - 22 minutes, or until cake insert comes out clean.

Step 8

In the bowl of a standing mixer, beat together cream cheese and butter until smooth.

Step 9

With the mixer running on low, add icing sugar one cup at a time. Add milk and vanilla.

Step 10

Beat on high until frosting is fluffy.

Step 11

Separate frosting into two small bowls. Colour one bowl purple and one bowl pink.

Step 12

Fit the piping bag with a Wilton 2D (drop flower) tip. Fill one side of the piping bag with the pink frosting and the other side with purple. I find it easiest to fill the piping bag with an offset spatula. Do not mix the colours inside the piping bag to ensure a two-tone frosting.

Step 13

Once the cupcakes have cooled, use a pastry brush and brush on a thin layer of the lilac syrup.

Step 14

Start at the centre of the cupcake, pipe dollops of the frosting using the 2D tip. continue piping around the centre dollop until you reach the edge of the cupcake.

Step 15

Repeat with the remainder of the cupcakes.

Step 16

If any point the frosting is too soft, chill the piping bag in the fridge for fifteen minutes and continue piping.