For the buttermilk pancake, preheat the oven to 200 degrees. Separate the eggs. Mix yolks with buttermilk and flour until smooth.
Beat the egg whites with salt and sugar until stiff and fold into the buttermilk mixture. Heat the butter in a heat-resistant pan and pour in the pancake mixture.
Top with the blueberries. Put the Schmarren in the oven and bake for about 8 minutes. Cut in half, turn and bake for another 5 minutes.
Remove from the oven, cut into pieces and serve with the buttermilk pancakes sprinkled with granulated sugar.