Preheat the oven to 350 degrees F. Prepare a 9x5 bread pan by lining with parchment paper. Lightly grease the pan.
Begin by mashing the banana. Mix in the wet ingredients: eggs, Greek yogurt, brown sugar, coconut oil, and vanilla extract. Use an electric mixer to blend it together.
In a separate bowl, whisk together flour, PBfit, baking soda, baking powder, cinnamon, and sea salt.
Add the dry ingredients to the wet and mix together until no dry pockets remain. If using any add-ins, fold in them in here. Using a rubber spatula, pour into the prepared pan. Smooth out the top and place in the oven.
Bake for 50-55 minutes or until the center is completely baked through. Keep an eye on the banana bread at around the 40 minute mark and add foil if the top is browning too quickly.
Once removed from the oven, let cool completely (around 30 minutes), until slicing.