Because the Middle Ages love you and want you to be happy, the late medieval nobility invented an entire meal of evening drunk snacking.

Today in English, a "banquet" is a lavish meal to celebrate something or other. Medieval food historian Johanna van Winter, however, has traced the evolution of the word back to the 14th century in Burgundian sources. In 1337 and 1369, at least, a "banquet" wasn't a separate meal at all! It was merely an extra last course tacked onto dinner at fancy, multi-day noble/royal feasts. According to Winter, the typical "dessert" banquet consisted of a boar's head.

By the mid-fifteenth century, however, the meaning of banquet had shifted. Banquet had become its own meal! While it had once appended the last big meal of the day, it was now its own big meal, to finish off a night of politicking and drinking and dancing. Furthermore, as the wedding menus Winter studied indicated, it took on a quite different nature from the earlier multi-multi-multi course proper feasts. During the daytime meals, servants would circulate with each course in proper hierarchical order by exquisitely arranged table, codes of manners fully in effect.

The nighttime banquet was different. All of its food was laid out on tables for guests to select from as they wanted. In some cases, the tables wouldn't even be in the formal dining room at all--perhaps they would be outside under some kind of awning or pavilion-type roof, if the temperature permitted.

The food listed in the menus seems like typical feast fare:

A first dish...a ‘cretonnée de lart’ (veal or kid baked in lard with mashed peas or beans, egg yolks and spices), a stew with cinnamon, and venison with cloves. The second dish mentions peacocks, swans, herons, rabbits with a spiced sauce, and partridges with sugar. The third dish contained stuffed capons with cream, pigeon pie, and kid. For the fourth, we have eagles, pears in spiced sweet wine, gilded slices of sweetmeat, jelly, and cress. The fifth and final dish was cream, almonds, nuts, pears, and sweets.

From 1571, a Dutch banquet for a chivalric order's gathering involved:

the banquet should consist of four dishes with meat in aspic, four dishes with hazelnuts, four dishes with pancakes and wafers, four with baked apples, four with a salad of lettuce or red cabbage, five dishes with sweets, three with thick rice porridge, four with cookies with a hole, and four with chestnuts.

As for alcohol? Burgundian Duke Philip the Good hosted a 1454 feast whose banquet starred a perpetual wine fountain.

These late medieval and early modern banquets, moreover, seem to have developed a reputation for particular gluttony and raucousness. There is a famous allegorical play written around 1480 but not printed until the 16th century called, and needing no translation, La condemnacion de banquet. Personified Dinner, Supper, and Banquet are called to account in court for the harm they do to people's lives. The play is partially, maybe mostly, a laundry list of all the horrible maladies caused by gluttony.

The verdict? Dinner and Supper are allowed to stay. Banquet--the late night meal of debauchery--receives the death penalty.

I would post our usual warning that so far there have been a large number of incorrect, speculative, or otherwise disallowed comments, but that would be giving too much credit to most of the removed comments. It looks like people are using this opportunity to make some late night drunk junk comments. Fun of course, but not appreciated on /r/AskHistorians.

As always, before you attempt to answer the question, keep in mind our rules concerning in-depth and comprehensive responses. Answers that do not meet the standards we ask for will be removed, and posters who break the rules of the subreddit admonished as applicable.

Additionally, it is unfair to the OP to further derail this thread with off topic conversation, so if anyone has further questions or concerns, I would ask that they be directed to modmail, or a META thread. Thank you!