1478, Andrea del Verrocchio, The Virgin and Child with Two Angels -- National Gallery (London)

From the museum label: Verrocchio ran an active workshop.

Here, he has delegated the design and execution of the Christ Child, the angel holding him, and the curtains pulled back to reveal the scene to a pupil, Lorenzo di Credi, who worked with him from about 1473 until Verrocchio's death.

Done