Wendy,
I usually replace sugar/oil/butter about equally with their applesauce,
apple juice, or banana counterparts. Sometimes this affects the
consistency a bit (obviously), so I compensate by adjusting the amount of
other liquids or adding more flour, etc., in future attempts.
For cookies and such, it's pretty easy... I just mix whatever amount of
ripe, ripe bananas I have and a can of concentrated applejuice, and then
add flour/oats until it hits a good consistency.
--Dave
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