Peel the bananas and slice them. Keep it in the freezer for 2 hours.
In a saucepan, heat water and sugar on medium flame.
Once hot, turn the flame off and add coffee powder. Mix it well and keep aside to cool down.
Place the frozen banana slices, yoghurt and brewed coffee in the jar of a food processor. Blend until smooth.
Add honey and chopped walnuts, pulse to combine.
Pour it into a freezer safe container. Freeze overnight.
Take it out of the freezer 20-25 minutes before you want to serve. Scoop out and serve in bowls. Drizzle honey and garnish with chopped walnuts.