Heat the oven to 325°F.
Sift together the flour, baking soda, cinnamon and salt. Set aside.
In the bowl of a stand mixer fitted with a whip attachment, beat the sugar and eggs on medium speed until light and fluffy, about 5 minutes. (Or whip by hand with an electric , about 8 minutes.)
With the mixer on low speed, slowly drizzle in the oil. Be sure not to pour the oil in all at once; add it slowly so that it has time to incorporate into the eggs and doesn’t deflate the air you’ve just beaten into the batter.
Add the mashed bananas, creme fraiche and vanilla and mix on low speed until just combined. Fold in the dry ingredients and nuts by hand until thoroughly combined, so there are no more flour streaks in the batter. Do not overmix.
Pour the batter into a buttered 9-by-5-inch loaf pan and bake for 55 to 70 minutes, until the top of the banana bread is golden brown and springs back when you poke it in the middle.
Let cool for at least 30 minutes and then pop out of the pan and serve.
Keeps for 2 to 3 days at room temperature, tightly wrapped. Or store in the freezer, tightly wrapped in plastic, for up to 2 weeks and defrost overnight at room temperature.
Makes one 9-inch loaf.