Pine nuts are the edible seeds produced by pinecones. Most pine nuts are too small to make it worth the time and trouble to harvest; only a few species of pine nuts are large enough to make it worthwhile. First, they have to be extracted from the scales of the pine cones, and then the hard outer shells have to be removed. Unless you really want to forage for your own, it’s probably best to just buy them already shelled at the store!