In a bowl, whisk together flour, baking powder, salt, and black pepper. This ensures even distribution and a fluffier pancake.
In another bowl, beat the egg with milk and melted butter. Add mustard if using. Slowly fold the wet ingredients into the dry mixture.
Gently stir in the grated cheese and chopped chives. Be careful not to overmix—the batter should stay light and airy.
Place a non-stick skillet over medium heat. Lightly grease it with butter or oil to prevent sticking and add flavor.
Scoop batter into the pan, making small pancakes. Cook 2-3 minutes per side until golden brown and cooked through.
Stack pancakes on a plate, keeping them warm in a low oven if making multiple batches.