Add the Greek yogurt and cottage cheese to a mixing bowl. If you prefer a smooth cheesecake texture, blend them for a few seconds before mixing. If you like a bit of natural texture, simply whisk them together as they are.
Sprinkle the whey protein powder evenly over the top of the yogurt mixture. Whisk or beat with a hand mixer until everything becomes thick, creamy, and fluffy. If the mixture becomes too thick, add a splash of cold milk or water until it reaches a smooth mousse-like consistency.
Stir in the vanilla extract, lemon zest, and sweetener if you want extra sweetness. Mix until everything is fully combined and fragrant.
Gently fold in the chopped cherries with a spatula. Leave some pieces whole for juicy bites or mash a few for a richer cherry flavor and natural color.
Chill the mixture in the refrigerator for 20–30 minutes. This helps the fluff thicken into a creamy, dessert-like texture.
Spoon the fluff into bowls, cups, or jars. Add optional toppings such as extra cherries, crushed graham crackers, shaved dark chocolate, or lemon zest. Enjoy immediately or store in the fridge for up to 3 days.