Preheat oven to 425°. Place a medium cast-iron skillet in oven to preheat.
In a blender, blend eggs, flours, milk, sugar substitute, lemon zest until smooth and foamy, about 2 minutes.
Place butter into the preheated skillet and return to oven until butter is melted, Next pour batter into center of skillet. Top with blueberries.
Bake until golden brown and puffed, 20 to 23 minutes. Let cool 5 minutes.
Sprinkle with Lakanto Powdered Sugar Substitute before serving. Can serve with extra butter, pancake syrup, jam or whatever you like!
This makes 4 servings. On Weight Watchers, each serving is 4 WW Points. (This does not include extra butter, syrup etc.) Enjoy!