I'd like to make muffins that are rich yet high-fiber. However, the recipes I've seen are either rich OR high-fiber. I don't want to skimp on the eggs or butter, but most of the recipes calling for whole-wheat flour, bran, or flax tend to be low-fat as well.
How possible is it to take a full-fat rich muffin recipe and substitute wheat flour for white flour? And if I want to add a lot of ground flaxseed, should I adjust quantities of other ingredients or adjust the preparation method in some way?