Agnes Marshall dedicated considerable effort to refining ice cream recipes and techniques, focusing on ingredients, textures, and flavors that would appeal to Victorian palates. This laid the groundwork for her groundbreaking book.

'The Book of Ices' contained a vast collection of ice cream, sorbet, and other frozen dessert recipes, many of which were innovative for the time. It provided detailed instructions and emphasized the importance of using high-quality ingredients.

Marshall's work helped to popularize ice cream as a fashionable and desirable dessert among the Victorian elite. She made it more accessible and appealing through her recipes, publications, and demonstrations.