Musnad Ahmad 1153:1106

Yazid narrated to us, Ja'far ibn Burd informed us, he said: Umm Salim al-Rasibiyyah narrated to us, from Aisha, she said: When milk was brought to the Messenger of Allah, may Allah bless him and grant him peace, he would say: "How much blessing is in the house, or two blessings."