Lay equal portions of thinly sliced cooked ham (1/2 lb. total) and thinly sliced gouda cheese (7 oz. total) on a quarter section of each of 8 packaged crêpes (9 in.), then sprinkle lightly with ground nutmeg.
Fold crêpes in half over filling, then in half again to make a triangle. Set triangles, 3-layer side down, slightly apart in 2 nonstick or lightly oiled 10- by 15-inch pans.
Bake in a 400º oven until filling is hot in the center and crêpe edges are crisp, about 6 minutes; switch pan positions after 3 minutes. Transfer crêpes to plates. Serve crêpes topped with Dijon mstard (about 3 tablespoons total) and chopped parsley.