"What is Al-Kawthar?" He said: "That is a river that Allah has given me"- that is, in Paradise- 'whiter than milk and sweeter than honey. In it are birds whose necks are like the necks of camels." 'Umar said: "Indeed this is plump and luxurious then." So the Messenger of Allah ﷺ said, "Those who consume it are more plumb than it." (Using translation from Tirmidhī 2542)
"أعطيتُ نهرًا في الجنَّةِ يقالُ لَهُ الكوْثَرُ: ماؤه أشد بياضًا مِنَ اللبنِ، وأحْلَى مِنَ العسلِ، وأليَنُ من الزُّبدِ، فيه طيورٌ: أعناقُها كالجُزُرِ قال عمر: إنَّها لناعمةٌ: قال: أكْلهُا أَنْعَمُ مِنهَا".