I heard about this egg substitute and have been experimenting with it in various recipes. It's as follows:
5 TB plus 1 tsp water, divided
1 tsp unflavored gelatin
To make one "egg" (for substitution in baked goods), add 1 tsp of gelatin to 3 TB water and stir. Then, add 2 TB plus one teaspoon of boiling water to the mixture and stir.
NOTE: You may need to decrease the liquid in your recipe to make up for the additional liquid in the egg substitute. As a general rule, the reduction would be around 1/4 cup. In what little experimentation I have done, I found this to be somewhat accurate, but it really varies. I usually mix everything up then adjust. For example, in the case of brownies, I added additional flour to thicken the batter. Another time I didn't adjust at all and simply increased the baking time. This method produces very moist baked goods (especially compared to ground flax seed as an egg substitute), but you will need to experiment and adjust as best you can until you get it right.