Add the apple juice, lemon juice, monk fruit sweetener, grass-fed gelatin, and food coloring (if using) to a small saucepan over low heat. Whisk the mixture together until the gelatin powder has fully dissolved, about 2 minutes, then remove it from the heat.
Transfer the gelatin mixture to the molds, then refrigerate 30 minutes, or until the gummies are fully set. Pop the gummies out of the molds then serve/store as-is, or move on to the next step for the sour coating.
Mix together the monk fruit sweetener and citric acid in a bowl, then toss the gummies in the sour coating. Enjoy right away!