For every box of cake mix in pumpkin or orange You will need about 1/4 of the chocolate cake mix.
Spray the inside of a new wide mouth 1/2 pint jars. do as many as guests. Inside make a spider or write something scary. Do this in the lower 1/2 of jar.
The spider: I divided my dry Chocolate cake mix into 4 and using only 1/4 of the mix, added only enough water to make it a thick paste. Then putting it in a icing bag, or a plastic baggy with a cut end, pipe a spider on the lower 1/2 of the inside of the jar after you have spayed the inside lightly with oil. Make sure the paste is thick so the spider would stay in place.
Make pumpkin, orange or even white cake mix as directed.
Pour carefully just enough cake batter to go 1/2 way up jar.
Put jars on a cookie sheet. Put that into a preheated 350 Degree oven for 18-22 minutes watching to see they are done but not over done.
In the mean time make webs from the chocolate chips and butter, melted together. I like the microwave for that. do it is 30 second cycles. Look above for the picture to do that. Place then in the fridge after making.
Cool cakes completely. then top with webs before serving.