To make the cupcakes
1. Preheat the oven to 180°C/160° Fan, 350°F, Gas 4 while you combine the butter, Lyle's Golden Syrup, Golden Caster Sugar, flour, eggs and milk together in a bowl. Beat with a mixer until soft and creamy.
2. Divide the mixture between paper cases in a 12-hole muffin tin and bake on the middle shelf for 20-25 minutes until well risen and golden brown (and they spring back when lightly pressed with a finger). Transfer the cupcakes to a wire rack to cool while you make the buttercream.
To make the buttercream
1. Cream the sugar and butter together until the mixture is light and fluffy.
2. Fold in the dulce de leche, vanilla and salt until combined.
3. Separate out 3 tablespoons of the buttercream mixture into a separate bowl and add a small amount of green food colouring until it is the desired colour.
4. Add orange food colouring to the remainder (and majority) of the mixture until a pumpkin orange shade is achieved.
5. Using a piping bag, pipe a pumpkin shape with the orange buttercream, before using a new piping bag filled with green buttercream to add the leaves on top.
6. Allow to firm in the fridge for a few hours before serving.