Kue Renda Nutella Oatmeal

Bahan-bahan (16 porsi)

• 1 stick (8 tablespoons) salted butter
• 1/2 cup packed light brown sugar
• 1 cup rolled oats ((not instant))
• 1/4 cup all-purpose flour
• 1 teaspoon vanilla extract
• 1/2 teaspoon salt
• 1 large egg white
• 10 -14 tablespoons Nutella Chocolate Hazelnut Spread or melted chocolate