"Tu" (the Hebrew abbreviation of 15th) in the month of Shvat was set (Hillel's opinion generally overrules Shammai's) as the beginning of the tithable year for tree fruit: Calculating the tithe on fruit starts again for fruit that sets after that date.
One favorite dish of the Ashkenazim that survived the move from the shtetl to North America was the hearty mushroom-potato-barley soup called krupnick.
Here is the quintessential Jewish question: How do we emulate God? We are told that we were created by God. We are told that we have a divine spark within us.
"15th of Shevat;" New Year of the Trees; Jewish Arbor Day, which is a minor festival.