First off was the flour, which I knew I'd replace half with the wholemeal flour. Next was the butter. I'd already been researching various methods for replacing butter (see blog entry Fruit Sponge Cake), and I had seen some recipes for banana bread without butter. Applesauce + oil seemed a popular replacement as well as pureed vegetables or fruits. Unfortunately, the only applesauce that I could find was Bramley apple sauce which previous experience revealed it to be extremely tart and completely different from the American applesauce. I failed to locate any pureed or canned vegetables except tomatoes and potatoes. Lacking a blender, I decided to steam and mash my own sweet potatoes. Last was the fruit-flavored yogurt.
I used the Banana-Raspberry Bread recipe as a foundation; replaced half the flour with wholemeal, 1/4 of the sugar with brown sugar, milk with yogurt, and banana with steamed and mashed sweet potatoes; and used only baking powder (as I had no baking soda on hand).
Having never baked muffins before, this may have been too ambitious an attempt. Needless to say, it was a failed attempt. I'm pretty sure it was not overmixing as I'd been forewarned enough by all the "DO NOT OVERMIX"'s and "DO NOT OVERBAKE"'s I'd encountered. It seemed my batter may have been too wet, since the muffins did not rise and the insides were mushy as if undercooked. I was somewhat worried about the possibility, but I naively thought that quick breads could withstand higher moisture content. Wrong I certainly was! I didn't even realize how high my liquid ratio was; water seeped from the steamed sweet potatoes, yogurt, vegetable oil, fresh washed blackberries, and egg!So, my next attempt will be to eliminate the vegetable oil, decrease the yogurt and strain it through a paper towel, and bake the steamed sweet potatoes to help reduce the moisture. Let's see where this will take us...
