This is another delicious yet easy recipe from King Arthur Flour. The topping is amazing. The recipe says to bake for 35 minutes but I found it was not fully baked at that time. Then when you put the topping on, it sinks in the middle. I just baked it another 20 minutes instead of the 10 minutes it says for the topping. It was still delicious. The next time I made it, I baked it an extra 5-10 minutes until the cake tested done. Then I added the topping and baked as directed. Dig in as soon as it comes out of the oven or wait until it has cooled off. We used the topping recipe for another cake once and broiled it and it turned out great too.
http://www.kingarthurflour.com/recipes/farmhouse-buttermilk-cake-recipe
Farmhouse Buttermilk Cake