Gougères - Once Upon a Chef

Ingredients

• 1 cup low-fat milk (or ½ cup whole milk + ½ cup water)
• 1 stick (½ cup) unsalted butter, cut into 4 pieces
• 1 teaspoon salt
• 1 cup all-purpose flour, spooned into measuring cup and leveled-off
• 4 large eggs, at room temperature
• 1 large egg white, at room temperature
• 2 teaspoons Dijon mustard
• 2 cups coarsely grated cheese, such as Comté, Gruyère and/or sharp cheddar