noun
speed-eating contest
A competition where participants race to finish a large amount of food as quickly as possible.
夏祭りで早食い競争が行われた。
A speed-eating contest was held at the summer festival.
大食い refers to eating a large amount in general or a person who does so, while 早食い競争 specifically refers to a competitive event focused on speed.
Compound of 早食い (はやぐい, 'eating quickly') and 競争 (きょうそう, 'competition').