Preheat the oven to 350F. Grease a loaf pan or line it with parchment paper.
Make the batter:
Mash the bananas in a large bowl. Add the Greek yogurt, melted butter, and eggs, and whisk until combined. Then, add the sugar and vanilla, and mix to incorporate.
In a separate bowl, combine the flour, baking soda, and salt.
Gradually mix the dry ingredients into the wet ingredients bowl until just combined. Add the blueberries to the bowl and gently fold them into the batter using a spatula. Pour the batter into the prepared loaf pan.
Optional: Slice a banana in half lengthwise and place it on top of the batter.
Bake:
Bake for 55 minutes until a toothpick inserted in the center comes out clean. After 40 minutes, check the bread. If the top of the loaf is getting too brown, cover it with a piece of tin foil and keep baking.
Remove the banana bread from the oven. Allow it to cool down for 15 minutes before removing it from the pan and cutting it into slices.