Apricot-Black Currant Upside-Down Cake

I don't usually bake with butter as some of us are supposed to watch their cholesterol intake but we had friends over for dinner and, with three lean teenagers and a four-year old also at the table, I decided to forget about restrictions and go for it.
The fact is that, like Eve in Paradise, I had been sorely tempted. In my case, the snake was the recently published Rustic Fruit Desserts by Cory Schreiber and Julie Richardson, a luscious cookbook which features seasonal fruit (the recipes are arranged by season) and simple ingredients.
If I had a bakery, such desserts are the ones I would like to offer. I can see them already in my mind's eyes, colorful but quiet, unassuming to the point of being coy but, oh, so delicious!
I adapted the recipe somewhat as I used more apricots than indicated and tucked black currants between the apricot halves (both because I love the taste of "cassis" and to make the cake more visually interesting). I also used a saucepan and a 10-inch springform cake pan as I didn't have the recommended cast-iron skillet in which to both make the caramel topping and bake the cake.
I had taken advantage of a recent daytrip across the river to Kingston, Ontario, to stock up on frozen apricots and currants at Tara Natural Foods. Using fresh fruit might have been better but, unless you grow them or have access to a pick-your-own farm, both are either too expensive or unavailable in the northern region where our summer cabin is located.


Ingredients:
For the fruit topping
6 apricots (or as many as necessary to fill the bottom of a 10-inch cake pan), sliced in half and pitted (or frozen, straight from the freezer)
a handful of black currants (if unavailable, use blueberries instead), optional
56 g unsalted butter, melted
107 g sugar (the recipe calls for brown sugar but I didn't have any on hand)
For the cake
157 g unbleached all-purpose flour
106 g fine cornmeal (I only had coarse cornmeal on hand and it worked fine. I even think I liked it better that way than I would with fine cornmeal)
1.5 tsp baking powder
1/4 tsp baking soda
113 g unsalted butter, at room temperature
127 g granulated sugar
2 eggs
1 tsp pure vanilla extract
167 g buttermilk

Method:
Preheat the oven to 350 F/177 CMelt the butter in a small saucepan over medium heat and add the sugarStir until dissolved and goldenPour into an oil-sprayed 10-inch springform pan (I had lined the bottom with parchment paper)Place the apricots cut side down on the bottom of the cake, add the currants or blueberries (if using)Whisk the flour, cornmeal, baking powder, baking soda and salt together in a bowl. Ising a mixer (handheld or stand), cream the butter and sugar together on medium-high speed for 3 to 5 minutes, until light and fluffyAdd the eggs one at a time, scraping down the sides of the bowl after each addition, then stir in the vanillaStir in the flour mixture in three additions, alternating with the buttermilk in two additions, scraping the sides of the bowl occasionallyGently spread the batter over the fruit and bake in the middle of the oven for 45 minutes or until the center of the cake springs back lightly when touchedAllow the cake to rest about 20 minutes before flipping it over. This cake is best eaten the day it is made but the leftovers (covered with plastic wrap) make a yummy breakfast.