Dulce de Leche Cupcakes

Ingredients

• 1 & 1/4 cup (170 g) cake flour (refer to the Notes section below for cake flour substitute)
• 1/2 cup (100 g) granulated sugar
• 1/2 cup (95 g) packed brown sugar
• 1/2 tsp baking powder
• 1/4 tsp baking soda
• 3/4 tsp cinnamon
• 1/2 tsp ground nutmeg
• 1/4 tsp ground cloves
• 1/4 tsp ground ginger
• 1/4 tsp fine salt
• 1/4 cup (55 g) unsalted butter, room temperature
• 1/4 cup (60 ml) canola oil
• 2 large egg whites, room temperature
• 1 tsp vanilla extract
• 1/2 cup (110 g) sour cream, room temperature
• 1/3 cup (80 ml) whole milk, room temperature
• 1/4 cup (50 g) granulated sugar
• 1 tsp cinnamon
• 2 tbsp (30g) unsalted butter, melted
• 1 cup (230 g) unsalted butter
• 2 cups confectioners’ sugar
• 1/8 tsp fine salt
• 1 & 1/4 cups (380 g) dulce de leche, divided (half for filling and half for buttercream)