Line loaf pan with parchment paper and set aside.
Mix peanut butter, maple syrup, and vanilla extract in a medium bowl.
Add in Cheerios and mix until coated.
Transfer mixture to loaf pan and press down until evenly distributed.
Place in freezer to harden while you make the milk topping.
Mix coconut oil, maple syrup and soy milk until combined. Make sure your coconut oil is room temperature. This will take a little bit of time until it is thoroughly mixed.
Pour milk mixture over Cheerio base and freeze for 1-2 hours until set.
Once bars are set, cut and enjoy!