Ingredients:
- 1.5 cups (190 g) all-purpose flour
- 0.75 cup (150 g) granulated cane sugar
- 1.5 tsp (7 g) baking powder
- 0.5 tsp (3 g) salt
- 0.5 cup (115 g) unsalted butter, softened
- 2 large eggs, room temperature
- 1 cup (240 ml) low-fat buttermilk
- 1 tsp (5 ml) pure vanilla extract
- 0.5 cup (115 g) unsalted butter, softened
- 2 cups (240 g) powdered sugar
- 2 tbsp (30 ml) heavy cream
- 0.5 tsp (3 g) vanilla bean paste
- Gel food coloring (pink or blue)
- 1 cup (225 g) unsalted butter, softened
- 3 cups (360 g) powdered sugar
- 2 tbsp (30 ml) heavy cream
- 1 tsp (5 ml) vanilla extract
- 1 pinch (1 g) salt
Instructions:
- Preheat the oven to 350°F (180°C). Line 30 cupcake liners in standard 12-slot tins.
- Cream the 0.5 cup butter and the 0.75 cup sugar until pale and fluffy.
- Beat in the eggs one at a time, then the 1 tsp vanilla extract.
- In a separate bowl, whisk the flour, baking powder and salt. Add the dry ingredients and the 1 cup buttermilk to the butter mixture alternately, stirring until smooth.
- Divide the batter evenly among the 30 liners, filling each two-thirds full.
- Bake for 22–28 minutes, until the tops spring back when lightly touched and a toothpick inserted in the centre comes out clean.
- Transfer to wire racks and cool completely, for at least 1 hour, before coring.
- Beat the 0.5 cup butter, 2 cups powdered sugar, 2 tbsp heavy cream and 0.5 tsp vanilla bean paste until velvety.
- Divide the filling into two bowls. Tint one bowl pink and one blue with gel food coloring.
- Beat the 1 cup butter, 3 cups powdered sugar, 2 tbsp heavy cream, 1 tsp vanilla extract and the pinch of salt until light and fluffy.
- Using an apple corer (0.5 inch) or small round piping tip, remove the centre of each cooled cupcake, stopping about 0.5 inch from the bottom.
- Pipe the pink or blue filling into the cored centres, half of the cupcakes with each colour.
- Pipe a generous swirl of the white frosting over each cupcake, completely sealing the hole.