Though the Iron Lady is recognized for her vast political and economic impacts, her culinary contribution to the world is less known. 
As a chemist for food manufacturer J. Lyons and Co. in the 1940s, Thatcher was part of the British research team that made soft-serve ice possible, according to The Washington Post's Caitlin Dewey, citing a 1983 New Scientist article
Thatcher, and colleagues, invented a way to add more air into the ice cream so that it was less dense and used less ingredients, which also made it more cost-effective.
The new formula also made it possible to push ice cream through a machine, producing the signature soft-serve swirl that we're familiar with today.