Compared to modern Japanese cuisine, cuisine of the time was very austere. Modern Japanese cuisine has inherited elements of the food of the time, but has added a lot of foreign influence (Western, Chinese, Korean), and become much more rice-centred and meat/fish heavy.

Little meat was eaten except by the upper classes. Most meat was game rather than domesticated animals.

A typical peasant meal was mixed grains (unpolished rice, millet, barley) cooked with vegetables (chopped radish roots or radish greens or various wild greens). Poorer peasants could only rarely afford to eat rice.

A typical middle-class urban meal was a bowl of rice, a bowl of soup (perhaps miso soup), pickled vegetables, and a side-dish. The side-dish was usually vegetables or tofu, sometimes fish, very rarely meat. Fish might appear as a side-dish less than weekly, depending on wealth. Vegetables were often simmered. Fish would be simmered or grilled. For breakfast, just rice, soup and pickles, with no side-dish.

A typical elite meal would be a bowl of rice, pickles, soup, fish. The fish could be preserved (pickled or dried), simmered, grilled, or sashimi, either as a standalone dish or as part of a salad. (e.g., "fish salad" (namasu) of sliced fish and vegetables with a dressing). Soups would often be fancier than those of poorer folk, and could vary from simple vegetable soups to crane soup or heron soup. For a fancy meal, there would be 2-3 soups, and a number of side-dishes (which, at least later, in the Edo Period, was often regulated by sumptuary laws to 5 or fewer).

Beef was rarely eaten. Imperial and Shogunal edicts against beef-eating were issued from the 8th century through to the Edo Period, for a variety of claimed or apparent reasons: religious, preservation of cattle for traction in agriculture, reduction of foreign influence. Horse meat was also often banned, to preserve livestock. Pigs only became significant in Japanese farming in the 17th century, in Kyushu (Chinese influence), and only spread outside Kyushu much later (but wild boar did appear on the table). Chicken was rarely eaten (mostly for medicinal purposes), and most birds that appeared on the menu were game.

Frying, baking, and sugar candies entered Japanese cuisine in the Edo Period.

For food of the time, especially elite food, see E. C. Rath, Food and Fantasy in Early Modern Japan, University of California Press, 2010.

For the evolution of modern Japanese cuisine (much of which occurred in the 20th century), see K. J. Cwiertka, Modern Japanese Cuisine, Reaktion Books, 2006.

Between the two of these, one can see both what was eaten in the Sengoku Jidai and the differences between it and modern cuisine. Cwiertka also gives relevant detail on peasant food, which remained very similar to its Sengoku Jidai ancestor into the 20th century in many parts of Japan. (If anybody can suggest other good sources, it would be much appreciated.)

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