"I entered the house of the Prophet with him and there was some bread and vinegar. The Messenger of Allah said: 'Eat; what a good condiment is vinegar.'" (Using translation from Nasāʾī 3796)   

دَخَلْتُ مَعَ النَّبِيِّ ﷺ بَيْتَهُ فَإِذَا فَلْقٌ وَخَلٌّ قَالَ رَسُولُ اللهِ ﷺ «كُلْ فَنِعْمَ الْأُدُمُ هُوَ»