The quickbread ratio: 2 parts flour and liquid, 1 part egg and butter.
That will give you a perfect muffin or, baked in a loaf pan, a quickbread. Now, you also need to have a little technique and common sense. A teaspoon of baking powder for every 5 ounces (cup) of flour is needed for leavening, a pinch of salt for flavor, but that’s it.
If you want a lemon-lime cake, add lemon and lime juice and zest; vanilla is always good, or add lemon and poppyseeds, add cranberry and orange, blueberries, bananas. Make a savory quick bread with cumin coriander and ginger to accompany a dal. (Secret: If you season the batter with a little sugar and vanilla and pour it on a griddle, you have perfect pancakes. That savory quickbread suggestion? Pour it over corn or peas, just enough to bind them, spoon the mixture into hot oil for amazing fritters).
(source: Mark Ruhlman)