This recipe is for soft, spiced banana cupcakes that have been filled with dulce de leche, piped with vanilla frosting, and decorated with more dulce de leche and chocolate shavings.
Preheat the oven to 180°C (350°F) and line 2 cupcake trays with 24 cupcake papers.
Combine the softened butter, oil, and sugar in a bowl of an electric mixer fitted with a paddle attachment. Beat at medium-high speed until light in color and creamy.
Add the eggs one at a time. Be sure to scrape down the sides of the bowl with a rubber spatula and beat well between each addition.
Sift together the flour, salt, and mixed spice.
Add the mashed bananas, vanilla, and buttermilk to a jug and stir to combine.
Add the wet ingredients, and flour mixture to the cupcake batter by alternating between the two. Starting with the flour and ending with the banana mixture. Once added, scrape down the sides of the bowl with a spatula and mix again to ensure everything is well combined.
Use an ice cream scoop to fill the cupcake liners two-thirds of the way up the liner. Bake in a preheated oven for about 15 - 20 minutes or until a light golden brown and a cake tester inserted into the center of the cupcake comes out clean. Cool completely on a wire rack.
Vanilla Buttercream
In a bowl of an electric mixer fitted with a paddle attachment, add the butter and icing sugar. Beat at medium speed until the mixture looks like fine breadcrumbs.
In a jug combine the milk and vanilla, with the mixer's motor running at low speed slowly add the milk mixture. Continue until it has all been added.
Increase the speed of the mixer to medium-high. Beat until light and fluffy, scraping down the sides of the bowl often. Add the frosting to a piping bag fitted with your chosen attachment.
Decorate
Use a fork to loosen and smooth out the dulce de leche, if necessary. Once smooth, add it to a piping bag. Use an apple corer to remove the center of each cupcake and fill the middle of the cupcakes with the dulce de leche.
Pipe a swirl of the fluffy vanilla frosting onto each cupcake. Then pipe a dot of caramel over the frosting.
Grate milk chocolate over the top of each cupcake, serve, and enjoy!