Add the cottage cheese, Greek yogurt, vanilla extract, lemon juice, and your chosen sweetener to a blender, making sure the ingredients are evenly distributed so they blend smoothly from the start.

Blend on high speed until the mixture becomes completely smooth and creamy, stopping once or twice to scrape down the sides and bottom of the blender so no lumps remain. Continue blending until the texture looks glossy and thick, similar to soft-serve ice cream.

Add the frozen blueberries to the blender. For a fully blended blueberry cheesecake flavor, blend again until the color and texture are uniform. If you prefer visible blueberry swirls, pulse the blender briefly just until the berries are partially broken down.

Taste the mixture and adjust the sweetness if needed, keeping in mind that frozen desserts taste slightly less sweet once set. Blend again for a few seconds to fully incorporate any added sweetener.

Transfer the mixture into a freezer-safe container and use a spatula to smooth the top evenly, which helps it freeze uniformly and prevents ice crystals from forming.

Cover the container tightly with a lid or wrap and place it in the freezer for 2–3 hours, until the ice cream is firm but still easy to scoop.

Remove the container from the freezer and let it rest at room temperature for 5–10 minutes before serving, allowing the texture to soften slightly for the creamiest, smoothest scoops.