Mix cashew butter, raspberries, and water until combined.
Add protein powder, cacao, and baking powder. Mix well.
Separate into 6 pieces. Form each into a ball, and press to flatten.
Press each cookie in erythritol crystals, and lay on parchment-lined cookie sheet.
Bake for 8-10 minutes, until firm.
Let cool, and enjoy! Store extras in the refrigerator.
Notes
A note about substitutions: because different types of protein powders bake up very differently, I would only recommend pea and rice protein powders (or blends of pea or rice proteins) in this recipe.