United States · Food · Hard
Answer: Fannie Farmer — Fannie Merritt Farmer's 1896 cookbook introduced precise level measurements (a teaspoon, a cup) instead of vague directions like 'a lump of butter the size of an egg.'
Fannie Merritt Farmer's 1896 cookbook introduced precise level measurements (a teaspoon, a cup) instead of vague directions like 'a lump of butter the size of an egg.'