From the horse's mouth -- here is what the Oxford English Dictionary has to say.
transitive. colloquial (orig. U.S.). to bring home the bacon: to succeed in an undertaking; to achieve the desired victory, result, etc.; (later also) to supply material support for a household. Also to bring home the gravy. Cf. to deliver the goods at good adj., n., adv., & int. Phrases P.7a.
The origin of the phrase has been traced to a telegram sent to the boxer Joe Gans (1874–1910) by his mother ahead of a fight in Goldfield, Nevada (in which he was victorious): see quot. bring v..
1906 Before the fight Gans received this telegram from his mother: ‘Joe, the eyes of the world are on you. Everybody says you ought to win. Peter Jackson will tell me the news, and you bring home the bacon.’
Buffalo (New York) Courier 4 September 1/2 Citation details for Buffalo (New York) Courier
(Also -- PSA to all, if you have a library card, you can log into the OED online.
https://www.dclibrary.org/research-and-learn/oxford-english-dictionary)