Muhammad bin Ka'b (may Allah have mercy on him) says: I came to Sayyiduna Anas bin Malik (may Allah be pleased with him) in Ramadan while he intended to travel; his mount had been saddled, he had put on his travelling clothes, and sunset was near. He called for food and ate from it, then mounted. I said to him: "Is this the Sunnah?" He said: "Yes."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8180