The main ingredient was malt which Bothilda made of wheat or barley. Use clean grain washed and let stand in water overnight.
The soaked grain was next placed between clean muslin, covered with blankets and put in a dark place to sprout. When three sprouts or roots appeared, it was ready to brown in the oven, dry and grind.
A wooden tub, used only for beer making was kept clean and free from bran, soap, seeds and other contaminants. The tub had a hole in the bottom in which a peg was inserted. Three bunches of straw were tied together to fit over the peg, the straw acting as a strainer. The ground malt was put in the tub, boiling water added and the mixture let stand overnight. Then the peg was loosened and the liquid allowed to drip into buckets. The tub was rinsed, and the straw bunches cleaned and readied for later use.
The strained liquid was warmed and replaced in the tub, along with sugar, hops and yarrow which had grown wild in the fields and dandelion roots, which had been boiled, carefully strained and the juice added till just the desired flavor was obtained. As the right temperature was reached, the special brewer's yeast was added. When a thick brown foam formed on top of the beer, it was carefully skimmed off and the brew was ready to bottle.