Sayyidah Aishah (may Allah be pleased with her) said: On any day that the Prophet (peace and blessings be upon him) came to my house after Asr, he (peace and blessings be upon him) would certainly pray two rak'ahs.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4399