Grease a bread pan liberally with coconut oil or butter and set aside.
In a medium sized bowl, beat banana, coconut oil, honey, yogurt, eggs, vanilla, baking soda, salt, and cinnamon together with a hand mixer.*
Fold in flax and flour until just mixed in, being careful not to over mix. Remove beaters and add nuts, stirring lightly to distribute them evenly.
Bake for approximately 50 minutes until a toothpick comes out mostly clean (best if not over baked). Let cool in pan for 10 minutes before removing and cooling fully before slicing. Keep in a covered container or wrapped tightly for up to 4 days. You can also freeze slices or an entire loaf to be defrosted and eaten later.
Notes
*I normally use a glass mixing bowl so that I can melt the coconut oil directly in it and then beat the bananas in. *If excluding nuts, the bread may bake more quickly so check it at 40 minutes.