In a large mixing bowl, combine the 1 1/4 cups rolled oats and 1/2 cup protein powder until evenly mixed.
In a microwave-safe bowl, add 3/4 cup peanut butter and 1/4 cup maple syrup; microwave briefly until the peanut butter softens and the mixture is pourable, about 20–30 seconds, stirring once.
Pour the peanut butter and maple syrup mixture into the dry ingredients and stir until fully combined and a sticky dough forms.
Using clean hands, scoop and roll the mixture into small balls and place them on a lined plate or tray.
Refrigerate the balls for at least 1 hour to firm up before serving.
Notes
Keep refrigerated for best texture.
Press tightly when rolling to help them hold together.
Use a scoop for uniform-sized balls.
Swap peanut butter for another nut butter if desired.
Let cool slightly if the peanut butter is very hot before handling.