Add the cottage cheese, almond milk, casein, PBfit, 1 tbsp peanut butter, sweetener, vanilla, and salt to a blender. Blend on high for 45 to 60 seconds until completely smooth. No cottage cheese curds should be hiding.
Pour the base into a Ninja Creami pint container. Tap it on the counter a few times to pop air bubbles. Put the lid on.
Freeze FLAT (important, not tilted) for at least 24 hours. Tilted freezing gives you a lopsided puck and the Creami will scream at you.
Pop the frozen pint into the outer bowl of the Creami and lock in the blade paddle.
Run the Lite Ice Cream setting. Do not use regular Ice Cream, it will over-work the base and make it grainy with this protein ratio.
After the first spin, if the texture looks dry, powdery, or crumbly around the edges (normal for high protein bases), pour in 1 to 2 tablespoons of almond milk and run the Re-spin cycle. This is what turns it from protein science experiment into soft serve.
Poke a 1.5 inch hole straight down through the center with a spoon. Drop the chopped Reeses cups into the hole.
Run the Mix-In setting once. This folds the chunks through without pulverizing them.
Scoop into two bowls (or eat straight out of the pint, also valid). Drizzle the warm peanut butter over the top. Sprinkle a tiny pinch of flaky sea salt. Eat immediately.