Wash the spinach and place in a blender or food processor. Add the egg, butter, flour and milk, and blend well for 1 minute. Pour into a bowl and allow to sit for 30 minutes.
Wash the mushrooms and put in blender or food processor along with the ham, sour cream and paprika. Puree and set aside.
Heat a crepe pan, or small non-stick skillet over medium heat until a drop of water jumps in the pan. Put 1 tablespoon of crepe batter into the pan and tilt the pan to spread the batter evenly. Turn down the heat. Crepe should be very thin so it will cook in less than a minute. The crepes do not need to be turned. Remove the crepe and continue with the rest of the batter, one at a time. You should thin the batter with 1-2 tablespoons of water as you make the crepes, because the batter will thicken as it sits. You want to keep the crepes very thin!
Place each crepe in an oven dish as you make them. Spread each crepe with the ham and mushroom filling, and fold.
Sprinkle the grated cheese over the top, and heat in pre-heated 375F oven for 2-5 minutes.