Preheat the oven to 350°F. Line two, 8 or 9-inch loaf pans with parchment paper, or spray the inside of the pans with a non-stick baking spray.
Preparing the Bread Batter:
Place the softened butter, sugar, and vanilla extract into a large mixing bowl. Use a hand mixer with beater attached (or a stand mixer on low speed) and cream together the butter and sugar for a few minutes, until light and fluffy.
Next, add the Greek yogurt (or sour cream) and mix again for a minute. Add the eggs next and mix again for a few minutes, until the eggs are well beaten.
Pour in the maple syrup. After adding the maple syrup, the mixture will look separated; this is okay!
In a separate bowl, combine the dry ingredients: flour, baking powder, baking soda, and salt. Sift the dry ingredients into the wet batter, then mix for a few minutes until well combined.
Cut the bananas into small chunks, then place them onto a plate and use a fork to mash the bananas into a puree. Add the puree to the batter, along with the diced pistachios and chocolate chips.
Use a spatula to fold in the bananas, nuts, and chocolate, until the batter is uniform.
Baking Instructions:
Divide the prepared bread batter evenly between the two lined bread pans. Sprinkle extra chocolate chips over the top, if desired.
Bake the banana bread at 350°F for 60 to 70 minutes, or until a toothpick inserted into the center comes out clean. Space the loaf pans apart at least 6 inches for even baking.
After baking, keep the bread in the pans for 5 minutes, then use the parchment paper to gently lift the bread out of the pans and onto a wire rack to cool. Remove the parchment paper before cooling.
Serving & Storing:
I recommend letting the bread cool for at least 30 minutes to 1 hour before enjoying. This bread is fantastic when enjoyed warm! Use a serrated knife to slice the bread.
Allow the bread to cool completely before storing or wrapping. Wrap the bread in plastic wrap and keep it stored at room temperature for up to 2 days. For longer storage, refrigerate or freeze the bread.