Prep the pan: Heat oven to 350°F (175°C). Line a 9x5-inch loaf pan with parchment, leaving overhang for easy lifting.
Lightly grease the sides.
Mash the bananas: In a large bowl, mash bananas until mostly smooth with a few small lumps. You should have about 1 1/4 to 1 1/2 cups.
Whisk wet ingredients: Add eggs, Greek yogurt, olive oil, maple syrup, and vanilla. Whisk until smooth and well combined.
Mix dry ingredients: In a separate bowl, whisk flour, baking soda, baking powder, salt, and cinnamon.
Combine gently: Add dry ingredients to wet.
Stir with a spatula just until no dry streaks remain. Do not overmix.
Fold in add-ins: If using nuts, seeds, or chocolate chips, fold them in now. The batter will be thick and scoopable.
Fill the pan: Scrape batter into the loaf pan and smooth the top.
Add a few thin banana slices and a light sprinkle of turbinado sugar if you like.
Bake: Place on the center rack and bake 50–60 minutes, or until a toothpick comes out clean or with a few moist crumbs. If the top browns too fast, tent loosely with foil for the last 10–15 minutes.
Cool: Let cool in the pan 10–15 minutes, then lift out by the parchment and cool completely on a rack before slicing. This helps the crumb set.
Slice and serve: Cut into 10–12 slices.
Enjoy plain, warmed, or toasted with a smear of almond butter.