Heat oven to 350 degrees F. Butter a 6-cup (9×5-inch) loaf pan (see note up top if yours is smaller) or coat it with a nonstick cooking spray and set aside.
Melt the butter in a big bowl. Whisk in the brown sugar until it looks smooth. Stir in the mashed bananas. Add the eggs and vanilla and whisk again.
Sprinkle the salt, cinnamon, nutmeg (if you’re using it), baking soda, and baking powder evenly over the top. Whisk everything together really well so there aren’t any dry spots. Then whisk around the bowl 10 more times—just to be safe!
Add the flour and stir until it’s all mixed in. Pour the batter into your loaf pan. It should come up to about half an inch from the top.Sprinkle raw sugar generously over the top—it may look like a lot, but it bakes into a beautifully sweet, crunchy crust. If you have flaky sea salt, a small pinch on top adds a lovely contrast. Bake banana bread for 55 to 65 minutes. It is done when a toothpick or skewer inserted into the bread is batter-free — be sure to check the upper third as well, near the rim of the pan; that’s where I’d find the unbaked pockets of batter hanging out. The bread will get very dark but will not taste burnt.
Let the banana bread cool in the pan. It tastes great on the first day, but it becomes even more moist and flavorful on the second and third—if you can wait that long before digging in!
To store: Keep the banana bread in the pan without covering it. After slicing, press foil against the cut side but leave the top open—so the crunchy top stays crisp. It lasts up to 5 days at room temp, maybe a week in the fridge, but it usually disappears in 2–3 days anyway.
