For this cake, filling and buttercream I used two different recipes and tweaked a couple of the ingredients slightly to get the results I wanted.
For the cake and filling I used Mother Thyme's recipe (pictured on the left) and for the zesty lemon buttercream I used Kitty Cat Stevens' recipe (pictured on the right). Both are great recipes and I'd highly recommend either!
For the cake: I didn't change any of the ingredients in Mother Thyme's cake recipe, except I added about 1 1/2 cups of fresh blueberries (tossed in a little flour) to the batter. I used three 8" cake pans, greased with butter and coated in flour, and baked them at 325 degrees (compared to 350 degrees in her recipe) for a little bit longer time so that they wouldn't rise too much. I learned that tip from this wonderful post on how to build a layer cake from Completely Delicious!
For the filling: I tweaked Mother Thyme's recipe quite a bit, so here's my modified list of ingredients...
- 3 cups of fresh blueberries
- 3/4 cup water
- 1 cup sugar
- 3 TBSP cornstarch
- juice of one lemon (about two tablespoons depending on your lemon)
- zest of two lemons
For the buttercream: I ended up adding an extra tablespoon of lemon juice (3 tablespoons total) because my buttercream was still a bit too stiff. The zestiness of all that lemon zest and juice really cut the sweetness of the powdered sugar, so the buttercream wasn't sickeningly sweet like some can be!
I did the traditional crumb coat followed by a second layer of buttercream, and had enough buttercream left over for Antoine to devour. And since I had so much excess blueberry filling left and, obviously even more blueberries in my fridge, I tried to pretty up the top a bit...mainly because I still need a good piping bag.
Voila! Everyone really seemed to enjoy the cake...it was completely gone (save one piece set aside for Antoine) by the end of the day. Most of the blueberries still sunk to the bottom of the cake pans (even with the coating of flour) because they were so heavy, but that's okay. As far as cake goes, it was pretty tasty. Sweet, but not sickeningly so, and zesty!