Preheat the oven to 350°F. Line a standard loaf pan with parchment paper and grease all sides. Set aside.

In a medium bowl, whisk together the sugar and eggs for about 30 seconds until fluffy and light yellow. This dissolves the sugar but also incorporates air into the batter. Add the oil, sour cream, vanilla extract and hot coffee. Whisk to combine. Then, mix in the smashed bananas.

Whisk in the flour, baking soda and salt until no more flour is visible. Then, fold in the chopped walnuts.Note: Measure flour by weight in grams instead of cups. Shop my exact scale here. (affiliate link) If you don't have a scale, fluff the flour with a fork in its bag or container, then spoon it into the measuring cup before leveling off with a flat edge. Do not scoop directly into the flour bag. This will add way too much flour to the batter, making it dry! Toggle back from US Customary to Metric conversion in my ingredients section above to find the weight in grams.Note: Chocolate chips are a delicious addition to my Banana Coffee Cake. Substitute half of the walnuts with chocolate chips to prevent the loaf from becoming too dense.

Bake for 57-60 minutes until a toothpick in inserted to the center and it comes out clean. Do not overbake.

While the loaf bakes, combine the hot water and instant coffee. Whisk together with the powdered sugar. It may seem like a lot but most of the icing will drip off. It will thicken as it sets. Note: If using drip coffee, substitute my ratios for 1 Tablespoon of hot water and 1 Tablespoon of hot coffee.

Place the loaf on a cooling wrack with parchment paper or a pan underneath. Drizzle the icing over the hot loaf and let it cool completely before slicing. The warmth from the loaf will thin out the icing.Note: To get the same glazed look in my photos, pour the icing over the loaf while its still warm.