Kue Mentega Lengket

Bahan-bahan (24 porsi)

• 8 ounces cream cheese (room temperature)
• ½ cup powdered sugar (divided)
• ½ cup unsalted butter (room temperature)
• 1 teaspoon ekstrak vanila
• 1 large telur
• 1 campuran kue mentega kuning kotak (atau campuran kue kuning)