There are only a few times of year I venture to make a cake like this, one so massive and stately that it practically demands a crowd. It is, I think, the platonic ideal of coffee cake. There are layers of plush, fine-crumbed, buttery cake. There is a ribbon of melted chocolate in the center. There are silky slices of pears, and just enough cinnamon. And the whole giant cake (it weighs nearly 4 pounds) is crowned with a generous layer of cocoa streusel.
Despite this cake’s grandiosity (yes, it’s true, it calls for a pound of butter), it’s relatively simple to make. To ensure the batter comes together smoothly, bring your butter, eggs and sour cream to room temperature before you begin. If you’d like, the streusel and chocolate filling can be prepared ahead and refrigerated until you’re ready to make the cake (up to three or four days). In fact, the whole cake can be assembled the night before you plan to serve it, wrapped well in plastic and refrigerated, should you want to bake the cake in the morning and serve it warm from the oven (It’s worth noting that the baked cake is so rich and buttery that it keeps for many days at room temperature.)