Place 8 (6-ounce) ramekins into a baking dish then pour mixture into ramekins. Next, pour boiling water in baking dish until water reaches halfway up the sides of the ramekins. Bake for 40-50 minutes, checking at the 40-minute mark. Centers should be set, with a slight wobble when you tap the sides. Cool completely on wire rack, then refrigerate for at least 4 hours.
When ready to serve, top each custard with a teaspoon of sugar. Carefully torch in a circular motion, 4 inches away from the top, until sugar melts and turns an amber color.
Dip banana slices in sugar, add on top and caramelize the bananas.