Musnad Ahmad 30:863

Sufyan narrated to us, from Ibn Abi Salih—meaning Suhayl—from his father, from Abu Hurayrah, informing them of that from the Prophet, peace and blessings of Allah be upon him: "When the servant of one of you prepares his food for him, and he has been spared its heat and its smoke, let him have him sit with him and eat. If he refuses, then let him take a morsel and turn it over [in the sauce or food], then let him give it to him."