Here's what you'll need!
300g  white chocolate
200g butter or margarine (or 3/4 cup plus 3 tablespoons butter OR 1 3/4 cups margarine)
250millilitres or 1 cup of milk (4%)
165g or 2/3 cup plus 2 tsp brown sugar
2 tsp vanilla

2 eggs
1 2/3 cup or 267g  plain or all-purpose flour
1 tsp baking powder

2 tsp vanilla
2 eggs
1 2/3 cup or 267g (9.42 ounces) plain or all-purpose flour
1 tsp baking powder

Melt together  white chocolate and butter in the microwave or using a double boiler on the stovetop. Then add your brown sugar, followed by the milk and vanilla, then whisk in the eggs, the flour and baking powder.
Using a jug pour into cupcake cases and bake in the oven at 160°C (or 320°F) until springy when touched (you can insert a knife into the middle of one of them, if it comes out clean, than thay are done!).

Caramel frosting recipe
2 cups Dulce de leche thick caramel
1 cup butter at room temperature (or 220g butter or 116g  margarine)
Whip together the butter and dulce de leche on high speed for 5 minutes, until it looks smooth and fluffy. Pipe onto your cooled cupcakes.