In a large mixing bowl, combine the rolled oats, oat bran, graham cracker crumbs, protein powder, natvia sweetener and salt. Set aside.
In a small bowl, combine the nut butter of choice and brown rice syrup and microwave for 2 minutes, or until melted.
Pour the wet mixture into the dry and mix until well combined. Add the milk then slowly incorporate the mini marshmallows, as they will start to melt.
Form into palm sized cookies and lay on a baking sheet or plate. Evenly top each cookie with chocolate chips and freeze for an hour or refrigerate for 4 hours/overnight.
* I used Dandie's vegan mini marshmallows Avoid using a chocolate or cinnamon flavoured protein powder as it detracts from the s'mores taste. Similarly, try to stick to a mild tasting nut butter like cashew or almond. You can sub the brown rice syrup for honey (if not strictly vegan) or maple syrup, but add an extra 2 tablespoons. Depending on the protein powder of choice, you may need more milk