Whip heavy whipping cream until it looks like whipped cream.
Mix in sugar until incorporated.
Peel and slice banana.
Microwave the slices for 45 seconds. (This may vary by microwave. You are looking for something very soft, but not liquid.)
Mash the microwaved banana and let it come to room temperature.
Stir the banana and cacao nibs into the whipped cream.
Notes
Tip: Most recipes that call for bananas recommend that you use overripe bananas because they are extra sweet. This requires advance planning. If you have a spur of the moment desire to bake with bananas, you can microwave a not-so-ripe banana to bring out its sweetness.