Prepare box cake mix in round pans and cut according to diagram.

Assemble the layers with a layer of white frosting between the two, then add a thin layer of canned frosting (crumb coat). Put into the freezer for a couple hours. Finish it off with the rest of the frosting, smoothing it really well by misting it with water and smoothing with an icing spatula. Place back into the fridge.

Use the shortening to grease a large microwaveable bowl for the marshmallows, the mixer bowl, your dough hook, and a sturdy rubber spatula.

Sift the powdered sugar and reserve about one cup. Put the rest into the greased mixer bowl.

Put the marshmallows into the microwaveable bowl and add the water. Microwave in 30 second intervals until melted, stirring with rubber spatula in between intervals.

Add the melted marshmallows to the powdered sugar. Lock the mixer and cover the opening with plastic wrap to keep powdered sugar from coming out. Turn mixer on low and allow dough hook to do its thing. Keep mixing for several minutes until the sugar seems to have incorporated for the most part. If still sticky, begin adding reserved powdered sugar, you may use it all, you may not, depends on your weather conditions. It’s really humid here, so I used it all.

Fondant is ready when it balls up around your dough hook or when you can touch it and it’s still pliable but not sticky. Remove from the mixer and wrap in plastic wrap. Allow fondant to rest for a minimum of 2 hours, I think overnight was best.

To use the fondant, knead it several times, like you would bread dough, to get it to a workable consistency (much like that of Play-dough).

To add coloring, do not use liquid food coloring. Use paste or gel colorings to a handful of fondant, then mix that piece into a larger batch.

Cover work surface with cornstarch. Roll out fondant to 1/4″ thickness. Cover cake and trim excess.

Use black decorator gel to add webs.

Cut eyes from white and black fondant. Paste them together with a little water and place them on top of the cake. I used a tiny paintbrush dipped in water, squeezed out the excess and touched up the cake.

I drew out the eyes and cut them from fondant using my drawing.