In a large bowl, combine the flour and salt. Make a well in the center and add the eggs and water. Mix until a smooth dough forms. Knead the dough on a floured surface for about 5 minutes until it becomes elastic. Wrap in plastic wrap and let it rest for 30 minutes.
In a skillet, heat the olive oil over medium heat. Add the chopped onion and cook until soft and translucent. In a bowl, combine the ricotta cheese, Parmesan cheese, cooked spinach, nutmeg, and cooked onion. Season with salt and pepper to taste.
Roll out the dough on a floured surface to about 1/8-inch (3mm) thickness. Cut the dough into 3-inch (7.5cm) squares or circles.
Place a small spoonful of the filling in the center of each dough square or circle. Fold the dough over to form a half-moon shape or a triangle, pressing the edges to seal.
Bring a large pot of salted water to a boil. Cook the Schlutzkrapfen in batches, boiling them for about 3-4 minutes or until they float to the surface. Remove with a slotted spoon and drain.
In a skillet, melt the butter over medium heat. Add the cooked Schlutzkrapfen and sauté until lightly golden. Sprinkle with additional Parmesan cheese and garnish with chopped parsley.
Enjoy your meal!