I love dahl. In India (where my folks were from) there are an almost infinite set of combinations of dahls and corresponding phorons* (spice-seasoned anointing oil/ghee)  But I only know a handful of 'phorons' e.g.  Red lentils: Panchphoron + garlic and onion. Toor dahl: garlic + bay and mustards seeds.  Does anyone know where I can find out about more phorons? Do you know any yourself?    * a Bengali word - people from different parts of the sub-continent may use different names 
Oddly I have a coworker who bought a caramel apple and then left it in its plastic on his desk for about 4 years. We didn't photo document its decline but I should be able to recall.  After about a week the impalement point became quite unappealing. The area around the stick darkened and softened (it seemed, I didn't touch it). The rest of the skin looked fine.  After several years the caramel looked perfectly fine but misshapen and the apple had dried and shriveled inside of it.  Based on that, and my own experience, I would conclude that a refrigerated caramel apple would have about the same life as an uncarameled apple except for the core which would need to be avoided.  As for extending the life? Perhaps pour wax around the stick entry point to buy yourself a couple days? 