Preheat oven to 180°C (160°C for fan ovens), Gas Mark 4. Place the flour, condensed milk, egg, vanilla, buttery spread and baking powder in a large bowl and using an electric whisk, beat together until pale and fluffy.
Spoon mixture equally between the muffin cases. Bake for 15-18 minutes until springy and golden. Allow to cool. Beat icing sugar, buttery spread and vanilla with enough condensed milk to make a smooth creamy icing.
Using a sharp knife, cut a circle into the centre of the cupcakes to create a little pocket about 2.5cm deep. Set aside the cone shaped pieces. Divide the chocolate beans between the holes. Slice off a little of the cake from the cone so that it can fit on top of the filling.
Divide the icing between 2 bowls and beat a little colouring into each. Spoon the buttercream into a piping bag, a colour at a time, making sure one colour sits down one side and the other colour sits down the opposite side of the piping bag. Pipe on top of each cake.