She might be one of the most celebrated American chefs of the 20th century, but even the celebrated chef Julia Child used recipes when she cooked. Famous for the amount of detail she put into her cookbooks, Child often went through several stages when perfecting her recipes for her books.

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In 1961, Child published her first cookbook, Mastering the Art of French Cooking. Less than a decade later, she published a companion volume that tackled the difficult world of baking French breads. One of her most simple recipes, pain de mie, outlined how to make traditional white sandwich bread. It was a recipe that Child tinkered with throughout her career, making its final appearance in one of her last books, Julia’s Kitchen Wisdom, published in 2000.

Rayna Green, curator of Child’s kitchen at the National Museum of American History, sees Child’s recipes as a window into how the chef viewed the act of cooking. “She’s trying to get the best recipe together. She always said, ‘Do what I tell you, and you can cook like me.’”

Child might have implored others to follow her advice, but she often followed the advice of others in her own cooking. It wasn’t unheard of, Green explains, for Child to crack open a cookbook in her personal cooking. “If she wanted to do a béarnaise sauce she would look it up in Larousse before she whipped up the sauce that she’d probably done a thousand times,” Green notes.

Above, we’ve looked closely at Child’s handwritten recipe for pain de mie, exploring what the recipe can tell us about Child’s career and passion for cooking.