Einkorn Blueberry Upside Down Cake

Ingredients

1 ½ cup (180 g) Jovial All-Purpose Einkorn Flour or 1 cup (96 g) Jovial Einkorn Wheat Berries ground to whole wheat flour
1 ½ teaspoon baking powder
¼ teaspoon baking soda
⅛ teaspoon salt
zest from 1/2 lemon
8 tablespoons (113 g) unsalted butter, at room temperature, plus more for greasing the pan
¾ cup (150 g) sugar, plus 2 tablespoons (30g ) for dusting
2 large eggs
½ cup (122 g) whole milk yogurt
1 cup (120 g) fresh or frozen blueberries

Preheat the oven to 350°F. Butter an 8-inch square pan. Cut a piece of parchment paper 7-inches wide and place in the pan, creasing at the bottom of the pan and allowing the rest to hang over the edges. Lightly butter the parchment paper.
In a medium bowl, sift together the flour, baking powder, baking soda, and salt.
In a bowl of a standing mixer fitted with the paddle attachment, cream the butter on medium-low speed for 2 to 3 minutes. Add ¾ cup (150 g) of sugar and mix on medium-low for 1 minute, until the butter is whipped. Add the eggs and lemon zest and mix until just combined, scraping down the sides and the bottom of the bowl. Detach the bowl from the mixer.
Fold half of the flour mixture into the egg mixtures. Fold in half of the yogurt, then add the remaining flour and finish with the yogurt until just combined.
Transfer the batter to the baking pan. Add the blueberries on top, then dust the top with the remaining 2 tablespoons of sugar.
Bake for 37 to 40 minutes or until a toothpick inserted in the center of the cake comes out clean.
Let the cake cool in the pan on a rack for 15 minutes, then invert the cake on a serving dish. Carefully remove the parchment paper and serve.
Store in a sealed container at room temperature for up to 2 days.