Slice the banana thinly.
Line a baking tray with parchment paper.
Arrange the sliced bananas evenly on the parchment paper.
Spread Greek yogurt evenly over the bananas.
Sprinkle nuts or your preferred toppings evenly on top.
Place the tray in the freezer for 2 to 3 hours until set.
Cut the bark into bite-sized pieces and enjoy.