Blackberry Lemon Upside-Down Cake Layer Cake

The other night I became weirdly obsessed with the idea of making a layer cake out of upside-down cakes and could not rest until I had done just that.

Mind you, not splitting one upside-down cake layer into two, but rather baking one or two separate upside-down cakes and stacking them so that the glorious, jammy, caramelized fruit becomes a baked-in filling. 

My initial plan was to do a riff on Strawberry Shortcake, one of my favorite things on the planet, but the market near me had nothing but neglected, over-priced Strawberries. The blackberries on the other hand were looking pretty good for the end-of-summer, so I put my strawberry desire aside, and decided to go with . . . 

Blackberry-Lemon Upside-Down Cake Layer Cake
Serves 8

Preheat your oven to 350*
Prepare two 6" round cake pans. (Sometimes I just want a small cake, so I chose to bake this as two 6" layers. That said, this recipe can be easily doubled and baked in two 8" or 9" pans.)  Liberally butter both, but add a parchment round to the bottom of just one of the pans. 

200 g (1 c) granulated sugar
Zest of 1/2 large lemon
1 stick of unsalted butter, room temperature
188 g (1 1/2 c) all-purpose flour
1 1/2 tsp. baking powder
1/2 tsp. kosher salt
2 large eggs, room temperature
120 g (1/2 c) whole milk
1/2 tsp. vanilla extract

10 plump blackberries, fresh or frozen. If fresh, rinse lightly and let dry. If frozen, there is no need to defrost
1 tbsp granulated sugar

• Toss the blackberries with the granulated sugar and lay them out in the bottom of the pan without the parchment liner. Set aside with the other prepared pan.
• In a small bowl, whisk together the flour, baking powder, and salt. Set aside.
• In a glass measuring cup, add the milk and vanilla. Set aside.
• In the bowl of a stand mixer fitted with the paddle attachment, rub the lemon zest into the sugar until the oils are well distributed, then add the softened butter and cream on medium speed for 4-5 minutes until fluffy and lighter in color.
• Add the eggs, one at a time, beating on medium for one minute after each egg. Don't forget to stop and scrap the bowl!
• On low speed, alternately add the flour mixture and the milk mixture in three separate additions, beginning and ending with the flour mixture. Once the batter is mostly free of flour streaks, remove from the mixer and finish mixing with a light hand. 
• Divide the batter between the two pans as evenly as possible. The batter will come a little higher up in the pan with the blackberries.
* Put into the pre-heated oven and bake about 30 min. for the plain layer and 35 min. for the upside down layer. They are done with the sides begin to pull away from the pans and a toothpick test comes back with just a few crumbs attached. (Don't poke the toothpick all the way in, especially with regards to the upside down layer. Just 1/2 in or so should suffice.)
• Remove the pans from the oven and set on racks to cool for 5 min. before turning out of the pan to cool completely. Remember to let the upside-down layer cool with the fruit on top. 

Is lovely frosted with whipped cream. I tried out a new-to-me recipe for Stabilized Whipped Cream Frosting for this cake, but the next time I do it, I want to use simply plain, unsweetened whipped cream as I like less sweetness. 

This is an extremely versatile layer cake. As I noted above, the recipe can easily be doubled, but you can also switch up the fruit (the amount of which will depend on the fruit itself as well as the size of cake you want), omit the zest, change the flavoring, and/or make both layers upside-down cake . . . I'm thinking of trying out a three layer cake next using two upside-down layers!