Set your oven to 450°F and place a 12 inch cast iron skillet inside to preheat. The pan must be hot for the Dutch baby to puff properly.
Freshly mill your soft white wheat berries (or Kamut, if using).
In a blender or mixing bowl, combine the 4 large eggs, 160g milk (or buttermilk), 120g freshly milled flour, 2 tsp vanilla extract, and ½ tsp salt and 85g honey.
Mix until the batter is completely smooth and slightly airy. If there are lumps, keep blending or whisking until fully combined.
Allow the batter to sit for about 10 minutes while the oven and skillet finish preheating.
Once the oven is fully preheated, carefully remove the hot cast iron skillet, and add the butter. It should melt immediately. Tilt the pan to coat the bottom and sides evenly. Be cautious—it may splatter.
Once the butter has melter, quickly, but carefully, pour the rested batter into the buttered skillet and place it immediately back into the hot oven.
Bake for 18–22 minutes without opening the oven door. The Dutch baby will puff up and turn golden brown on top. Opening the oven can cause it to deflate.
The pancake will deflate shortly after coming out of the oven—this is completely normal. Serve hot with butter and warm syrup.