Preheat oven to 350 degrees. Coat loaf pan generously with nonstick spray.
Whisk flour, baking soda, and salt in a medium bowl.
Using an electric hand mixer or a stand mixer with the whisk attachment, beat brown sugar, labne, butter, and vanilla until light and fluffy, about 4 minutes. Add eggs one at a time, beating after each addition.
Reduce speed to low, add flour mixture, and mix until just combined. Add bananas and mix. Fold in the walnuts and scrape batter into the loaf pan. Smooth the top!
Bake for a total of 60 minutes. At 40 minutes, once your bread has beautiful color on top, take a large piece of foil and tent the loaf pan, leaving a generous space between the top of the bread and the foil. Remove from the oven after 20 more minutes.
Transfer to a wire rack and let bread cool in pan for 1 hour. Turn out the loaf, slice, and enjoy!