Add the Greek yogurt and cottage cheese to a food processor or high-speed blender.
Blend for 30–60 seconds, stopping to scrape down the sides as needed, until the cottage cheese is completely broken down and the mixture is smooth and creamy.
Add the vanilla protein powder, honey, vanilla extract, and cinnamon.
Blend again just until all the ingredients are fully combined and smooth.
Check the consistency. If the mixture is extremely thick, add 1 tablespoon of milk and blend briefly. Add a second tablespoon only if needed.
For a lighter texture, transfer the mixture to a chilled mixing bowl and beat with a hand mixer for 30–60 seconds to incorporate a little air.
Divide the yogurt fluff evenly between three airtight containers or small serving bowls.
Cover and refrigerate for at least 30 minutes so the mixture can become thicker and colder.
When ready to serve, top each portion with fresh berries or your preferred toppings.
Keep any unused portions refrigerated and enjoy within 3–4 days for the best quality.