Do not skip the peanut butter layer — it prevents ice crystals and adds flavor. For storage, keep in an airtight container in the freezer with parchment between layers; they last up to a month. Let sit at room temperature for 2–3 minutes if you prefer a softer bite. For a nut-free version, use sunflower seed butter or tahini. For white chocolate version, replace dark chocolate and skip salt, using toasted sesame seeds instead.