Preheat the oven to 350 F. Place a cast iron skillet in the oven as it pre-heats (any cast iron skillet 8-10 inches wide will work).

Divide egg yolks and egg whites. Add egg yolks, ricotta, milk, and vanilla to a medium mixing bowl. Whisk until combined. To the same bowl add flour, sugar, baking powder, and salt.

Add egg whites to the bowl of a stand mixer. Whip until stiff peaks form (this can also be done with a hand mixer).

Open the oven and add the butter to the cast iron skillet so it can melt while you finish the batter.

Add the whipped egg whites to the mixture and gently fold everything together.

Carefully remove the hot cast iron skillet from the oven. Swirl the pan to make sure the melted butter is covering most of the cast iron so the hotcake won't stick to the pan. Pour the batter into the cast iron skillet and transfer back to the oven.

Bake for 15-20 minutes, until toothpick comes out clean.

While the hotcake bakes, add 1 tbsp of butter to a pan over medium heat. Peel and cut the apple into small cubes. Add the apple and cinnamon to the pan. Stir until the cinnamon is well distributed. Add a splash of water, place a lid on the pot, and let it cook for 5 minutes, while the apples cook. Cook until the water is evaporated and the apples are cooked through.

You can also make the miso butter while the hotcake cooks. Add the softened butter and miso paste to a bowl. Use a hand mixer to whip until the butter and miso are fully combined.

When the hotcake is done baking, place a large plate upside down on top of the cast iron skillet. Carefully flip the cast iron skillet over, while keeping the plate held to the skillet. Once its flipped, slowly lift up the cast iron skillet, leaving the hotcake on the plate.

Top the hotcake with the cooked cinnamon apples and a scoop of miso butter. Add some maple syrup and enjoy!