Preheat oven to 350°F (175°C). Grease your loaf pan—future you will thank you.
Mash bananas in a large bowl until they look like baby food.
Whisk in melted butter, brown sugar, eggs, and vanilla until smooth.
In another bowl, whisk flour, cocoa powder, baking soda, and salt.
Slowly mix the dry ingredients into the banana mixture.
Pour in the espresso and instant coffee, stirring until just combined.
Fold in chocolate chips—or more if you believe in happiness.
Mix hazelnut spread, crushed hazelnuts, and heavy cream in a separate bowl.
Pour half the batter into the loaf pan.
Spread the hazelnut mixture evenly over the batter.
Top with the remaining batter and smooth the surface.
Bake for 55-60 minutes, or until a toothpick comes out mostly clean (ignore melted chocolate).
Let cool for 15 minutes, even though you’ll want to eat it immediately.
Slice, serve, and prepare for instant obsession.