Blueberry Cornmeal Skillet Cake

Preheat oven to 350 degrees and spay a 10-inch cast iron skillet with nonstick cooking spray.
In a large bowl, cream butter and sugar together with an electric mixer on medium speed for 2 minutes, until light and fluffy.
Add eggs and vanilla extract and beat until just combined.
In a separate bowl, whisk together the flour, cornmeal, baking powder, and sea salt.
Add the flour mixture to the wet ingredients and just before it all comes together, add the Greek yogurt (or sour cream). Stir just until smooth and flour is mixed well.
Pour half of the cake batter into the skillet, spreading it out evenly. Then, sprinkle the blueberries over the top. Using a spoon, dollop the remaining cake batter over the top of the blueberries until you've used all the batter.
Bake for 32 minutes, rotating the pan halfway through baking. Bake until a toothpick inserted in the center comes out clean. Do not overbake or it will be dry and crumbly. The cake will turn golden brown on top and puff up during baking. It will settle during cooling.
Cool completely on a wire rack before slicing. Then, slice into 8 pieces and serve by itself or top with some warm butter and a drizzle of honey.
Store skillet cake in an airtight container for 3-4 days or freeze for up to 3 months.