Preheat the oven to 350 degrees. Spray the sides and bottoms of 3 eight inch cake pans with baking spray and set aside.

In a medium bowl combine the flour, baking soda, baking powder, and salt. Mix well.

In a large bowl cream together the sugar, brown sugar, and butter. Mix until well combined.

Add in the eggs and mix well.

Stir the yogurt into the mixture.

Add half the flour mixture to the butter mixture and mix until just combined.

Add the milk and vanilla and mix until well combined.

Add the remaining flour mixture and mix until there are no lumps remaining.

Divide the batter into 3 small bowls. Dye one bowl green, and one bowl orange.

Add the black cocoa powder and 1-2 tablespoons of milk to the last bowl and mix well.

Pour one bowl of batter into each of the cake pans. Bake for 35-40 minutes or until a toothpick inserted into the center comes out clean.

Remove from the oven and allow to cool for 10 minutes. Run a knife around the edge and turn onto a wire rack to cool completely.

To make the frosting place the butter in a large mixing bowl and beat with a mixer on medium high speed until smooth.

Add in the powdered sugar 1/2 cup at a time mixing on medium speed or until smooth.

Add in the vanilla and milk and mix on high speed for 2 minutes or until fluffy.

Remove 1 1/2 cups of frosting and place them in a small bowl.

Dye the remaining large bowl of frosting black. You may need to use a lot of dye to make it a dark black color.

Place one layer on cake on a cake board and top with 3/4-1 cup of back frosting and smooth it on top.

Place a second layer on top of the first and top with 3/4-1 cup of back frosting and smooth it on top.

Place the last layer on top of the frosting. Using a butter knife or offset spatula to spread a thin layer of frosting all around the cake.

Place in freezer for 20 minutes.

Remove the cake from the freezer and use the butter knife or offset spatula to smooth frosting all over the cake.

To make the spiderwebs place the marhsmallows in a microwave safe bowl and heat for 20-30 seconds or until they get huge in the bowl.

Remove and stir until it looks like marshmallow cream.

Pull 1 tablespoon out of the bowl and carefully stretch it between several fingers on each hand and then carefully place on the cake to make spiderwebs. They will stick to your hands so gently remove the "web" so that it sticks to the cake.

Place sprinkles around the bottom edge of the cake.

To make the ghosts place the white frosting in a piping bag with a 1/2 inch to 1 inch opening. Pipe in a swirling mound to make the ghost shapes all along the top of the cake.

If you want to make the ghosts on the side place a little pressure on your piping bag to make a circle and then carefully pull it out in a swooping motion to make the tailend of the ghost.

Place any remaining black frosting in a piping bag with a very thin tip. Pipe on two dots for eyes and a large "o" shaped mouth on all of the ghosts.

Keep in an air tight container for up to 3 days.