Fluffy Pancakes

• 3/4 cup milk
• 2 tablespoons white vinegar
• 1 cup all-purpose flour
• 2 tablespoons white sugar
• 1 teaspoon baking powder
• 1/2 teaspoon baking soda
• 1/2 teaspoon salt
• 1 egg
• 2 tablespoons butter, melted cooking spray