Anas bin Sirin reported,

I asked Ibn Umar a similar question, and he added that one should perform the witr with a single rakah at the end of the night. In it he said, "Easy, easy! You are quite a hefty fellow."

Muslim 1762

Sahih

وحدثنا ابن المثنى وابن بشار قالا حدثنا محمد بن جعفر حدثنا شعبة

عن أنس بن سيرين قال

سألت ابن عمر بمثله وزاد ويوتر بركعة من آخر الليل وفيه فقال به به إنك لضخم

مسلم 1762صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Muslim
Book
Travelers' prayer and its shortening
Chapter
Night prayer is two rakats at a time and Witr is one rakat at the end of the night
Numbering
Darussalam 1762
Muslim 1762