Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius) and line a large baking sheet with parchment paper or a silicone baking mat.

In a large mixing bowl, whisk together the rolled oats, vanilla protein powder, ground cinnamon, baking soda, and salt until evenly distributed.

In a separate medium bowl, combine the mashed bananas, liquid egg whites, and vanilla extract, stirring until the mixture is cohesive.

Pour the wet ingredients into the bowl with the dry ingredients and stir with a spatula until a thick dough forms.

Gently fold the raisins into the cookie dough until they are evenly dispersed.

Using a standard cookie scoop or tablespoon, portion the dough into 12 equal mounds on the prepared baking sheet.

Lightly press down on each mound with the back of a spoon to flatten slightly, as these cookies do not spread significantly during baking.

Bake in the center rack of the oven for 10 to 12 minutes, or until the edges are firm and the tops are slightly golden.

Remove from the oven and allow the cookies to cool on the baking sheet for 5 minutes to set before transferring to a wire cooling rack.