Some desserts in jars are baked or otherwise prepared right in the jar, while others are spooned into jars. Either way, the sparkling and pretty vessel and the appealing treat it holds make for a beautiful presentation. Olmanson's clever and cute desserts are at once playful and well-crafted, appropriate for a kids' birthday one weekend (Peanut Butter Cup Cupcakes) and a grown-up gathering, the next (Neapolitan Cakes). The book includes chapters on...