In a blender, whirl eggs, milk and sour cream together. Then add flour, salt and sugar to the blender. Whirl until completely smooth. Batter will be thin and pourable.
Heat a medium-sized frying pan over medium heat. Oil the pan with about a teaspoon of oil (may need to add more later). When pan and oil are hot, pour 1/4c sized amounts of batter onto the center of the pan. Quickly but gently lift and swirl pan to spread batter to the edges. Batter should sizzle some in the oil if pan is hot enough. Cook about 60-90 seconds, until bottom begins to turn golden, then flip. Cook another 30-60 seconds until other side begins to brown. Fold in half and in half again to make a triangle. Set pancake aside and repeat with remaining batter.
Serve with melted butter, powdered sugar, and lingonberry jam (with sour cream, if desired).