Preheat your oven to 350°F (175°C). Grease a 9×5-inch loaf pan or line it with parchment. No excuses, this loaf is not sticking to your pan today.

In a bowl, mix the mashed bananas with melted butter until smooth. It should feel like a sigh of relief—moist and easy.

Stir in sugar, beaten egg, and vanilla. Mix until glossy and a little glossy is good; we’re not making soup here.

Sprinkle in baking soda and salt. Add flour gradually and fold just until you see no flour streaks. Don’t overmix—think gentle, not aggressive.

Fold in the 1/2 cup chopped walnuts. The batter should be thick but scoopable.

Pour batter into the prepared loaf pan. Smooth the top with a spatula so it bakes evenly.

Make the walnut crumble: combine flour, brown sugar, melted butter, and walnuts. It should resemble wet sand—crunchy, not mushy.

Sprinkle crumble evenly over the batter. A nice, chunky layer is what you’re aiming for.

Bake for 50–60 minutes, or until a toothpick comes out with a few moist crumbs. If the crumble is browning too fast, cover loosely with foil for the last 10–15 minutes.

Let it cool in the pan for about 15 minutes, then transfer to a wire rack to cool completely. Pro tip: slice after resting—clean cuts, no crumble chaos.