1-First Step: Get the oven and pan ready Start by preheating your oven to 350°F, or 160°C fan-forced. This temperature helps the loaf bake evenly without drying out too quickly. Line a loaf pan with scrunched parchment paper so the bread lifts out easily after baking. Using parchment with a little crinkling helps it fit the corners better. It also makes cleanup easier, which is always welcome on a busy day. If your oven tends to run cool or bakes unevenly, keep that in mind for later when checking the top for browning.

2-Second Step: Mix the dry ingredients In a medium bowl, whisk together the flour, sifted baking soda, kosher salt, cinnamon powder, and allspice powder. Whisking helps spread the leavening and spices evenly through the flour, so every slice tastes balanced. This step may look small, but it matters. If the baking soda is not mixed well, you can end up with uneven texture or spots of flavor. A quick whisk now helps the final loaf bake more evenly.

3-Third Step: Mash the bananas and build the wet mixture In a separate large bowl, mash the ripe bananas until mostly smooth. A few small chunks are fine if you like a little texture in the loaf. Add the brown sugar, eggs, egg yolk, sour cream, melted butter, vegetable oil, and vanilla extract. Stir until the mixture looks well combined. The batter will smell amazing already, thanks to the vanilla and bananas working together. Room temperature eggs mix in more smoothly, so the batter stays silky instead of lumpy.

4-Fourth Step: Bring the batter together gently Pour the dry mixture into the wet bowl and fold everything together with a spatula or wooden spoon. Stop mixing as soon as the flour disappears. A few streaks are better than overmixing, because too much stirring can make banana bread dense and tough. This is one of the biggest secrets to soft banana bread. Gentle folding keeps the crumb tender and helps the loaf bake up with a light, pleasant texture. If you are making banana recipes often, this is a habit worth keeping.

5-Fifth Step: Fill the pan and bake Pour the batter into the prepared loaf pan and smooth the top lightly. Bake for about 70 minutes, or until a skewer inserted into the center comes out clean or with just a few moist crumbs. If the top browns too fast, loosely cover it with foil near the end of baking. Because ovens vary, start checking near the end of the bake time. A loaf that is done in the center but still pale on top is common, especially if your oven runs cool. The foil trick helps protect the crust while the center finishes baking.

6-Final Step: Cool before slicing Let the banana bread cool in the pan for 10 minutes. Then lift it out carefully and move it to a wire rack. Cool for at least 1 hour before slicing so the crumb can settle and the loaf can hold together nicely. If you slice too soon, the middle may seem gummy even if the bread is fully baked. Cooling takes patience, but it gives you cleaner slices and better texture. That wait is hard, yes, but worth it.