1. 1. Prepare Your Baking Pan and Oven: Start by preheating your oven to 350 F (175 C). Grease and flour a 9×5 inch loaf pan, or line it with parchment paper for easy removal. This ensures your banana bread won’t stick and will release cleanly.

2. 2. Combine Dry Ingredients: In a medium bowl, whisk together the all-purpose flour, baking soda, salt, and ground cinnamon (if using). Make sure these are well combined to ensure even leavening throughout the bread.

3. 3. Mix Wet Ingredients: In a large bowl, whisk together the melted butter and granulated sugar until smooth. Then, beat in the large egg and vanilla extract until fully incorporated.

4. 4. Add Bananas and Sourdough Discard: To the wet ingredients, add the mashed ripe bananas and the unfed sourdough discard. Stir until just combined. The mixture might look a little lumpy from the bananas, which is perfectly fine.

5. 5. Combine Wet and Dry Mixtures: Gradually add the dry ingredient mixture to the wet ingredient mixture. Stir gently with a spatula or wooden spoon until just combined. Be careful not to overmix the batter; overmixing can lead to a tough banana bread. A few streaks of flour are okay.

6. 6. Pour into Pan and Bake: Pour the batter evenly into your prepared loaf pan. Place the pan in the preheated oven and bake for 50-60 minutes, or until a wooden skewer or toothpick inserted into the center of the loaf comes out clean. The top should be golden brown and spring back when lightly touched.

7. 7. Cool Before Slicing: Once baked, remove the loaf pan from the oven and let it cool in the pan on a wire rack for about 10-15 minutes. This allows the bread to set properly. Then, carefully remove the banana bread from the pan and let it cool completely on the wire rack before slicing and serving.