TIP: I cheated a little bit with this recipe. The base is exactly the same as the previous recipe. I just took 1/3 of the batter out before the toffee bits were added (and I added the espresso separately). Then I folded in the coconut and pecans. Two cakes with the same amount of work. I am going to give you the full recipe though. Feel free to make the batter divide it into 3, then mix in whatever you like to get 3 different cakes: chocolate chips, dried cranberries, swirl in peanut butter, etc.
German Chocolate Cake in a Jar
1/2 C butter (1 stick), softened
1 1/3 C brown sugar
1 tsp pure vanilla
1 1/3 C all-purpose flour
1/2 C unsweetened [dark] cocoa powder
2/3 tsp baking soda
1/2 tsp baking powder
1/4 tsp salt
1 C buttermilk (or regular milk, but not skim)1 C coconut
1 C chopped pecans
3-4 Tbsp "hot" caramel (the kind you need to heat up, not the really runny kind)
Beat butter and sugar together. Add eggs one at a time; fully incorporate. Add vanilla.
In a separate bowl, combine flour, cocoa, baking powder and soda, and salt. Stir gently with a fork or whisk to break up lumps. Sift if the mixture is still lumpy.
Alternately add flour mixture and buttermilk to butter and egg mixture. Do NOT over mix!
Gently fold in pecans and coconut.
Into each of 3 sterilized and greased canning jars, add two large spoonfuls of the batter. Add 1 heaping teaspoon of caramel to each jar. Do this two more times to create 3 layers. (Jars should not be more than 2/3 full.) Take a skewer or a long skinny spoon handle and swirl the batter and caramel together. Do not mix too much, you want the caramel to be swirled throughout.
Bake at 350 deg F for 35-45 minutes, until a toothpick inserted into the center comes out clean. Within 3 minutes of removing cakes from the oven, close with 2 part canning lid. In about 5-7 minutes you'll hear the lid pop, this means it is vacuum sealed. Allow to cool at room temp.