✓6 large, good-quality croissants
🥓6 slices thin-cut quality ham (e.g., Black Forest, honey ham)
🧀6 slices Gruyu00e8re cheese (or 1 cup shredded)
✓2 tbsp Dijon mustard
🥚1 large egg
🥛1 tbsp milk or water
✓Fresh chives or parsley, chopped (for garnish, optional)