In general, Medieval knights ate wild game, bread and vegetables. The specific type of game or vegetables depended upon the knight's geographical location and season. Dining practices also varied depending upon the classification of knighthood, such as the Knights Templar.
The Knights Templar were in the service of the church and, therefore, were required to adhere to strict rules according to their conduct including dietary restrictions. This meant that the Knights Templar did not usually participate in the grand feasts normally associated with royalty.
Rules 23 to 30 in "The Primitive Rules of the Templars" are specific to dietary rules and regulations. Rule 26, for example, visits the topic of eating meat. This rule states that Templar Knights should only eat meat three times a week because "the custom of eating flesh corrupts the body." Exceptions are made for this rule including Christmas, All Saints and the Assumption. Rule 27 specifies that vegetables and bread shall be eaten on the other non-meat days of the week.
From these rules, one gets an idea of what a knight's diet consisted of. Vegetables, such as cabbage, chickpeas and artichokes, as well as beans, broth, bread and fruits were plentiful throughout the week, especially on vegetarian days of the week. Meats included wild boar, deer, goats, partridges and sheep.