The name of this coffee cake comes from the convenience of assembling it the day before baking. If you can’t wait, by all means make and bake it right away; it’s wonderful either way. Generously topped with nuts, cinnamon sugar, and chocolate chips, it’s your ticket to a warm, luxurious morning.
Lightly grease a 9" x 13" metal pan (see tips below).
For the cake: In a large bowl, beat together the butter, sugars, baking powder, baking soda, salt, cinnamon, and vanilla, mixing until smooth. Add the eggs, one at a time, mixing until each is absorbed before adding the next.
Scrape down the bowl and add the flour, alternating with the sour cream until both are incorporated. Scrape the bowl again and mix for 30 seconds more. Transfer the batter to the prepared pan and smooth the top.
For the topping: Combine the brown sugar, cinnamon, nuts, and chips. Sprinkle over the batter. If desired, cover the pan and refrigerate overnight to bake the next morning.
If baking right away, preheat the oven to 350°F and bake for 35 to 40 minutes. If the cake was refrigerated overnight, uncover and bake for 40 to 45 minutes in a preheated 350°F oven. Remove from the oven and let cool on a rack before serving.
Store leftovers covered on the counter for up to 3 days; freeze for longer storage.
If you’re baking this in a glass or stoneware pan, the bake time will be at least 10 minutes longer, since they don’t conduct heat as efficiently as metal pans do.
