Before turning on your burner, add coconut milk, raw cacao powder, and tapioca starch to a medium saucepan and whisk to blend. Start cooking over medium heat, stirring frequently. Add collagen peptides and whisk, continuing to cook until mixture starts to bubble. Remove from heat.
Stir in peanut butter, maple syrup, and vanilla extract. Whisk until everything is combined. Allow to sit and come to room temperature, about 30 minutes.
Pour into a 9-by-5-inch loaf pan. Cover with parchment paper or aluminum foil and place in the freezer for at least 8 hours, or ideally overnight. Before serving, allow to soften 10 to 15 minutes. Scoop and enjoy!