Apple Butter Spice Cake with Cinnamon Crumble

Cake made with applesauce is good. Cake made with apple butter—which is basically just super-concentrated applesauce—is so, so much better. Moist and tender, with huge apple-y flavor, this simple spice cake is the ultimate bring-to-your-friend's-house baked good. If you really want your mind blown, serve the slices topped with more apple butter, a dollop of yogurt, and a dusting of cinnamon sugar.