Makes one 4" cheesecake.
A note about substitutions: because each type of protein powder has a distinct flavor and texture when baked, I would not try substituting different types of protein powders in this recipe. You may substitute other natural sweeteners for the stevia, if you like.
Also, Neufchâtel cheese is marketed as "⅓ less fat than cream cheese" here in the states. I stay away from the fat-free cream cheeses because of the additives.
And because this recipe is baked, regular vanilla extract should be fine.