Preheat oven to 400°F and grease a sheet pan or line with parchment paper.
In a large mixing bowl, add the protein pancake mix, almond milk, Greek yogurt, protein powder, cinnamon, vanilla extract, and salt.
Stir until fully combined and smooth.
Pour the batter evenly onto the prepared sheet pan and spread into an even layer.
Sprinkle frozen berries over the top and drizzle with peanut butter, if using.
Bake for 17–20 minutes, or until the center is set and the edges are lightly golden.
Remove from the oven, let cool slightly, then slice into squares and serve.