Diana Wynne Jones’ book Tough Guide to Fantasy Land (recommended for any fantasy/historical fantasy writer) is a hilarious riff on the fantasy genre. At one point, she mocks fantasy authors’ tendency for their adventurers to eat ‘stew’ in great quantity, which travelers would for the most part never do.
The classic example of this is when Sam, in Lord of the Rings, hauls those pots all the way to Mordor. A much more likely scenario would for him to have stashed a couple of sticks in his backpack to poke through those poor rabbits he takes from Gollum in order to roast them over the fire. Stew is far too much work.
So if not stew, then what?
Roasted meat over a spit, when possible. Stale bread. Berries or root vegetables gathered from the surrounding area. Salted, smoked, and dried meat that keeps for weeks (and tastes like it). Pioneers taking the Oregon trail across the country, where admittedly they had wagons, made corn pancakes on a griddle–but once again, that’s a heavy piece of equipment to carry.
People in the middle ages did eat a lot of stew, however. “The Vikings ate two main meals a day, one of which usually consisted of some kind of meal or porridge. The mainstay of everyday eating was the big kettle of stew (or skause– a Norse word!) containing whatever vegetables and meat were available, and added to day by day.” http://www.ydalir.co.uk/crafts/cook.htm
In Europe, “most medieval commoners cooked with only a large cauldron, known as the pot au feu, in the fireplace. Whatever they could find, they mixed it together in the pot and called it “stew.” Sometimes, it would be served with a slab of meat or even frumety. Frumety was a type of wheat pudding that surpassed bread in popularity during the Middle Ages, probably because it went so well with stew.” http://library.thinkquest.org/C005446/Food/English/middle_ages.html
For a long list of possible foods and dishes: http://shenanchie.tripod.com/medieval/med_3.htm
Medieval people also ate a lot of bread, but there is some question as to when the use of yeast became widespread. Peoples all over the world have eaten bread for thousands of years, since the cultivation of wheat.
This site states: “The custom of leavening the dough by the addition of a ferment was not universally adopted. For this reason, as the dough without leaven could only produce a heavy and indigestible bread, they made the bread very thin. These loaves served as plates for cutting up the other food upon, and when they became saturated with the sauce and gravy they were eaten as cakes. These were called trenchers. The use of trenchers remained long in fashion even at the most splendid banquets. It would be difficult to point out the exact period at which leavening bread was adopted in Europe, but we can assert that in the Middle Ages it was anything but general. Yeast was reserved for pastry, and it was only at the end of the sixteenth century that bakers used it for bread.”
At the same time, another site argues (http://www.breadinfo.com/history.shtml) that wheat was grown in Mesopotamia and Egypt, where it was first chewed, but then later pulverized it to make a paste. “Set over a fire, the paste hardened into a flat bread that kept for several days. It did not take much of a leap to discover leavened (raised) bread when yeast was accidentally introduced to the paste.
Instead of waiting for fortuitous circumstances to leaven their bread, people found that they could save a piece of dough from a batch of bread to put into the next day’s dough. This was the origin of sour-dough, a process still used today.
In Egypt, around 1000 BC, inquiring minds isolated yeast and were able to introduce the culture directly to their breads. Also a new strain of wheat was developed that allowed for refined white bread. This was the first truly modern bread. Up to thirty varieties of bread may have been popular in ancient Egypt.
It was also during this time that bread beer was developed. The bread was soaked in water and sweetened and the foamy liquor run off. Beer was as popular in ancient Egypt as it is in America today.” Bread was hugely important to the Roman Empire, and if nothing else, the mechanism for making it was brought to Britain and northern Europe with their conquest.
This opinion appears to be confirmed by this site: http://www.guglhupf.com/breaduca/history.html
For the Vikings: “Bread was made in great quantity and variety, both flat and risen. It’s uncertain if the Vikings had cultivated yeast as we know it, but they certainly made use of wild yeasts, raising agents such as buttermilk and sour milk, and the leftover yeast from brewing. They also used the ‘sourdough’ method, where a flour and water starter is left for several days to ferment. The most commonly grown cereal crops were oats, rye, and barley, but wheat was also widely used. Flour was also made from nuts (including acorns) or pulses (peas and beans), and even from tree bark. The inner layer of Birch bark, dried and ground, produces a flour with a sweet flavour and is highly nutritious. Bread could be flavoured with nuts, seeds, herbs, or cheese (yes, pizza is authentic!); or used to enclose fish or meat for baking it to succulent tenderness.” http://www.ydalir.co.uk/crafts/cook.htm