The energy provider said that more than one million households are facing a "heat or eat" dilemma in research conducted by YouGov for Npower.
The event called "Fuel" is a pop-up restaurant where Monroe, the chef, activist and food writer, gave diners the choice between warm food in freezing surroundings or no food in a warm environment.
Npower is also launching an independent charity, Npower Foundation, to help "alleviate the heat or eat dilemma" by expanding its Fuel Bank network which provides support for people in fuel crisis with two weeks of emergency gas and electricity.
The company is asking for donations to the charity and will match the first £50,000.
Matthew Cole, Npower’s head of social energy and trustee of the Npower Foundation, said: "Fuel Bank users tell us how a simple fuel voucher can make a world of difference to both them and their family members, not only providing power, heat and light, but also by reducing anxiety and worry.
"It was because of this that Npower was determined to act, to help more people above those benefitting from the existing £1m commitment to the Fuel Bank."