Mix flour, milk, eggs and salt until smooth. Soak for approx. 20 min. Rinse blueberries, sort out and drain well. Stir mineral water into pancake batter. Heat one tsp. fat in a large coated frying pan. Pour in 1/3 of the batter for four pancakes. Top each with a few blueberries.
Bake the pancakes on each side until golden brown and keep warm.
Bake 8 more pancakes in the same way. Mix cinnamon and sugar. Arrange three pancakes each with a tablespoon of sour cream or crème fraiche on dessert plates. Sprinkle everything with cinnamon-sugar and bring to the table with mint.