This lighter coffee cake is studded with those fresh, plump berries and was exceptionally moist - however, I thought it was almost on the verge of being too moist! When I was preparing the vanilla batter, there didn't seem to be anything unusual, but after I added the cup of buttermilk, I thought in my head that it looked just thick enough. While the recipe called for another 1/3 cup of buttermilk, I held back and compromised by tossing in two tablespoons instead.
The cake read like it was going to be a bit delicate, so rather than fuss with trying to get it out of a cake pan, I used a 9" springform pan instead (if you do use a 9" cake pan, you may need to increase the baking time slightly). Rather than mixing the batter with the blueberries, half of it is spread into the pan followed by a layer of berries, the rest of the batter and the other half of the berries. Just for added insurance against the berries wanting to sink, I tossed them with a couple teaspoons of flour to help suspend them in the batter. To give the cake a bit of sparkle and crunch, the top is scattered with coarse turbinado sugar right before going into the oven.
The flavor was right on and not too sweet - but, I thought the texture would have been a little better if I stuck with my instincts and left the buttermilk at 1 cup. It wasn't bad by any stretch of the imagination as we both enjoyed it - I just thought the cake was almost a little custard-y near the bottom (which I don't think would have been solved by baking longer as the crumb was not exceedingly wet).
Blueberry Coffee Cake