Take the cream cheese out of the refrigerator and let it sit at room temperature until completely softened. This usually takes about 30–45 minutes. Fully softened cream cheese is essential for achieving a smooth, lump-free texture in the pie filling.

Place the softened cream cheese and Greek yogurt into a mixing bowl. Using a hand mixer or whisk, beat them together until the mixture is completely smooth and creamy. Pause once or twice to scrape down the sides of the bowl so everything blends evenly.

Add the peanut butter, protein powder, cocoa powder, sweetener, and vanilla extract to the bowl. Start mixing at a low speed to prevent splashing, then continue gently until all the ingredients are fully incorporated and the mixture looks rich, thick, and uniform.

Continue mixing just until the filling is creamy and smooth, avoiding overmixing. Overmixing can thin the texture or introduce air, which can affect how the pie sets in the refrigerator.

Transfer the finished mixture into a pie dish or springform pan. Use a spatula to spread it evenly and smooth the top, creating a flat, neat surface for clean slices later.

Place the pie in the refrigerator and chill until fully set. This usually takes at least 2–3 hours, but chilling overnight will give the cleanest slices and the best cheesecake-like texture before serving.