Bread and pottage were the staple foods for most people throughout the Middle Ages in Western Europe.
Pottage (a sort of stew made from whatever ingredients--mostly vegetable--were obtainable) was eaten across social classes. Ingredients included a variety of vegetables (e.g. turnips, leeks, onions, cabbages, etc.), seasoned with herbs (e.g. parsley, sage, rosemary, and thyme), and could be thickened with grains (e.g. oats, rye, or barley). Meat could be added, if one could get it. Same for seasonings like salt, pepper, butter, or honey, even cinnamon if one could afford it. Pottages could be kept boiling for several days, adding more water and new ingredients to the "leftovers".
Breads were were made from flour ground from wheat, barley, or rye. There were a variety of breads, including shortbreads made with honey, flatbreads, sourdoughs, and malt breads.
While bread and pottage would be the staple foods, other foods were eaten as well. Fish was very common. Fish were frequently packed in salt to preserve them and shipped all over the place. Animals (including goats, pigs, cattle, sheep, and chickens) were raised for milk (and thus cheese), meat, and eggs. Fruits and nuts could be gotten in-season, including crab apples, blackberries, and wild strawberries (smaller and different flavor than what you can buy at the grocery store today).
All in all, the daily diet for your average freeman farmer could be rather monotonous, but had the potential to be comparatively healthy.