Knead the CMC into orange fondant until smooth and pliable. Roll thin strips to form the witch legs and cut them into desired lengths. Add whimsical black stripes and tiny shoes, then allow to set overnight.

Preheat your oven to 350°F (175°C). Cream together butter and sugar until fluffy. Add eggs one at a time while mixing. Combine dry ingredients, alternate with milk in the mixture, pour into a greased tin, and bake for 45-50 minutes.

Once the cake has cooled, beat the unsalted butter until creamy. Gradually mix in powdered sugar, then stir in vanilla extract and gel food coloring until a rich green hue is achieved.

Cut the cooled cake into circles that fit into jars. Layer cake and buttercream in jars, ending with buttercream to create a whimsical look.

Sprinkle festive Halloween-themed sprinkles on top, then insert fondant witch legs into the buttercream and arrange the jars for display.