I never saw the Prophet (ﷺ) seeking to fast on a day that he favored more than another except this day, the day of 'Ashura', and this month, meaning the month of Ramadan.
Sahih al-Bukhari Book 30, Hadith 111
← Previous Hadith The day of 'Ashura' was considered as `Id day by the Jews. So the Prophet (ﷺ) ordered, "I recommend you (Muslims) to fast on this day."

Sahih al-Bukhari Book 30, Hadith 110 Next Hadith → The Prophet (ﷺ) ordered a man from the tribe of Bani Aslam to announce amongst the people that whoever had eaten should fast the rest of the day, and whoever had not eaten should continue his fast, as that day was the day of 'Ashura' .

Sahih al-Bukhari Book 30, Hadith 112