In a large bowl, whisk together the flour and salt. Add the milk, sparkling water, eggs, and melted butter. Whisk until the batter is smooth and free of lumps. Let it rest for 10 minutes.

While the batter rests, prepare the filling. In a medium bowl, mash the farmer's cheese (or ricotta) with a fork. Mix in the sugar, vanilla extract, and orange zest until well combined.

Heat a non-stick skillet over medium heat and lightly brush with vegetable oil.

Pour about 1/4 cup of batter into the pan, tilting it in a circular motion to coat the bottom evenly. Cook for about 1-2 minutes until the edges lift and the bottom is golden.

Flip the crepe and cook for another 30 seconds on the other side. Transfer to a plate and repeat with the remaining batter.

To assemble, spread about 2 tablespoons of the cheese filling onto the center of each crepe. Fold the sides in and roll it up like a burrito, or simply fold it into a triangle.

Serve warm, topped with a dollop of sour cream and a dusting of powdered sugar.