What's the simplest whole-grain sourdough to make?

I like a fluffy crumb as well as anyone, but I like a simple process with fewer handlings of the dough, even more. I like low-gluten rye (and I know I can grow it), but wheat is fine too (though  I've had less success in my garden), and probably any grain is of interest to me. I'm already comfortable keeping a levain alive, even for many years (though I did just kill my current one). I'm open to high or low hydration, etc.

Whatever gets me as close to possible to: mix this freshly milled grain (blend?) with water and starter, let it rise somewhere that already exists (top of the fridge is OK, but I'm not going to buy or build a proofer), knead or stir it once, let it rise again, and bake -- and turns out a yummy, healthy bread that isn't so crumbly it can't be used for sandwiches (I'm not looking for grocery-store bread, I just don't want it so prone to falling apart that it's unusable).