Store in the fridge to keep them hard and so to maintain their shape. They will last for about a week. If you prefer another nut or seed butter, then please substitute with that. Just keep the quantities the same. Use a smooth, runny one if possible (to ensure they stick together). I have used dark chocolate which is at least 70% cocoa solids. This is what the nutritional information is based upon. *This post contains affiliate links. I may receive a small commission when you purchase through these links (at no extra cost to you). I only endorse products that I personally use or have tested.