Add butter and vanilla into a bowl of a mixer and beat for a few minutes until smooth and creamy. You can also use a hand held mixer with a large bowl.

Gently mix in powdered sugar a few cups at a time.

Then add cocoa powder, salt and cream. Mix well for about 1 minute.

Mix in several drops of black food gel. Keep adding color until you get the desired black.

If your frosting is too thick, add another tablespoon of cream until desired thickness.

Cover tightly and store in the refrigerator until ready to frost cupcakes.

Preheat oven to 350°F. Add black cupcake liners to a cupcake pan. Set aside.

In a bowl, combine the cake mix, oil, water and sour cream. Mix each egg one at a time. Mix on low for about 1 minute.

Mix in a few drops of black food gel if you desire then pour the batter into the cupcake liners.

Bake for 18-21 minutes. Allow the cupcakes to completely cool.

With a small sharp knife, cut a small chunk of cake out of each cupcake. Fill the hole with Halloween sprinkles. Replace the chunk of cake back into the cupcake.

Add the frosting into a piping bag fitted with an extra large round piping tip.

Pipe large swirls over the cupcakes and top with black sprinkles.