Ham and Cheese Pinwheels

Bahan-bahan (48 porsi)

• 2 sheets frozen puff pastry (thawed overnight in the refrigerator)
• 3 tablespoons Dijon mustard (divided)
• 12 slices thinly-sliced, good-quality deli ham (about 10 ounces)
• 2 cups freshly grated gruyere (Swiss, fontina, sharp cheddar, or similar melty cheese (about 5 ounces))
• Chopped fresh parsley (thyme, or chives (optional, for serving))