I have to agree with everyone - it will not work. If the cake is still hot, you can sometimes stick it back in, but the "chemical processes" have stopped so it may cook but not rise again. But totally cold, there is no chance of it cooking and the outsides will be dry.
Smell and look are good indicators; however you need to press the center to see if it pops back completely and quickly. Or use a toothpick in the center to make sure there is nothing "wet" coming out. Crumbs or a clean toothpick mean it is done. If the edges pull away from the pan and get brown and/or hard, they are overdone.
Hope that helps!
"Variety is not just the spice of life, it is the key to life" - Chef Michael Smith