Melt the black candy melts in the microwave for up to 30secs at a time, stirring between bouts until smooth. Add in 1 teaspoon of oil and stir until combined.
Using a teaspoon, spoon a small amount the melted black candy into each of the moulds and create swirls across the bottom using the tip of the spoon.
Melt the orange candy melts in the microwave (up to 30secs at a time), stirring between bouts until smooth. Add the remaining oil and the orange extract, stirring until you have a smooth melted candy.
Spoon ⅔ of the melted orange candy into the moulds carefully over and around the black candy swirls. Gently spread out the orange candy, with a spoon or brush, ensuring you cover the sides up to the edges. Tap your mould on the surface a few times to remove any air bubbles.
Push the popsicle sticks partway into the moulds (about ½ inch / 1-2 cm), then put in the fridge for 5-10mins to set.
Take the moulds from the fridge and fill them with cakesicle mix to just below the edges, pressing in gently to smooth the top.
Push the popsicle sticks in until they sit roughly ⅔ of the way into the mould, pressing the cakesicle mix down if needed. Put the moulds back in the fridge.
If needed, reheat the remaining orange candy melts in the microwave (15-30secs) to give a smooth melted candy and then remove the moulds from the fridge and spoon the candy melts over them, covering the cakesicle mix completely.
Place back into the fridge for 5-10mins, then carefully pop each cakesicle out of the mould. Run a sharp knife around the edges to clean up the sides if needed.