01 - Whisk flour and salt in a large bowl. Create a well in center, add eggs, and gradually whisk in milk and melted butter until smooth. Rest batter for 10 minutes.
02 - Heat nonstick pan over medium heat, brush with butter. Pour 1/4 cup batter, swirl to coat bottom thinly. Cook 1-2 minutes until edges lift and bottom golden. Flip 30 seconds. Transfer to plate. Repeat.
03 - Preheat oven to 350°F.
04 - Layer ham slices, spinach, cheese, crème fraîche, and black pepper on each crepe.
05 - Fold crepes into quarters or rolls. Arrange in baking dish, sprinkle remaining cheese on top.
06 - Bake 8-10 minutes until cheese melts. Serve hot, garnished with extra spinach or side salad if desired.