From: Linda Magee
Newsgroups: rec.food.cooking

Brownie Cakes In A Jar

2 Canning jars;wide mouth
1 c All-purpose flour
1 c Sugar
1/2 ts Baking soda
1/4 ts Ground cinnamon (optional)
1/3 c Butter;or Margarine
1/4 c -Water
3 tb Unsweetened cocoa powder
1/4 c Buttermilk
1 Egg; beaten
1/2 ts Vanilla extract
1/4 c Walnuts; finely chopped

Here's one you can start out with, it makes 2 jars. Every recipe technique is the same, just different ingredients.. Sterilize, two 1-pint straight-sided wide-mouth canning jars (specifically made for canning jams and jellies) lids and rings by boiling for 10 minutes (keep the lids and rings in the hot water until ready to use); set aside. In a small bowl stir together flour, sugar, baking soda and cinnamon, if desired. Set aside. In a medium saucepan combine butter or margarine, water and cocoa powder; heat and stir until butter or margarine is melted and mixture is well blended. Remove from heat; stir in flour mixture. Add buttermilk, egg and vanilla; beat by hand until smooth. Stir in nuts. Pour mixture into the prepared canning jars; place jars onto a cookie sheet. Preheat oven to 325-degrees. Bake for 35-40 minutes or until a pick inserted deep into each cake comes out clean. Remove cakes from the oven, one at a time. Place a lid, then a ring onto the jars and screw down tightly. USE HEAVY-DUTY MITTS, the jars ARE HOT!!

After cooled, store in refrigerator or freezer.

If you'd like to decorate them, place a wad of cotton in the center of each lid, then place a piece of decorative cloth, about 3-inches larger in circumference than the lid, (cut with pinking shears) on top of the cotton. Screw the ring back on (by this time the rings can be removed as the lids should be sealed). Use your imagination when decorating--a hot glue gun works wonders (dried flowers, ribbon, etc). These make WONDERFUL Christmas gifts.

Editor's Note:
Please be cautioned that no matter what you may read on the web about storing cakes in jars that the seal does not make them a 'canned' product. Info from the National Food Safety Database:

Canning Breads and Cakes
Angela M. Fraser
Canning breads and cakes is not true canning. It is the process of baking the product in canning jars and capping them as they come out of the oven. Usually, a weak seal will form as the product cools. This is not a shelf-stable product and so must be stored in the refrigerator or freezer to prevent microbial growth.

Title: Jar Cakes
Posted By: Rochelle, CA
Date: July 7th 2001
Board: recipelink.com Canning and Preserving

It is not recommended that jar cakes be kept longer than a couple of weeks and even then they should be refrigerated or frozen. The temperature in the batter doesn't get high enough and it doesn't penetrate the batter sufficiently to prevent bacteria from growing.