Green’s Dictionary of Slang

(orig. Irish) the essence of what a boy should be, a downright good fellow.

1689		‘King William’s Birthday’ in Ebsworth Bagford Ballads (1878) I 416: For he was the broth of a boy.
1823		Byron Don Juan canto VIII line 24: But Juan was quite ‘a broth of a boy’, a thing of impulse and a child of song .
1832		Sydney Monitor 25 Feb. 4/4: Phil Riley, a broth of a boy from the Emerald Isle, who, half seas over, had stood enjoying the fun, was sentenced to one hour in the stocks, for brandishing a shilelah and singing out, ‘to the rescue, to the rescue!’.
1838		Comic Almanack Mar. 131: Pat Murrough, your health – you’re a broth of a b’y!
1842		N.Y. Aurora 27 Apr. n.p.: Pat Kelly, a broth of a boy, with cheeks like thumping red potatoes.
1846		D. Corcoran Pickings from N.O. Picayune 192: Troth thin, yer a broth of a boy.
1847		Bell’s Life in Sydney 6 Feb. 2/6: A broth of a boy, who gave his name as Michael Carney.
1852		Bell’s Life in Sydney 12 June 3/2: The constable, a real broth of a boy.
1854		Delhi Sketch Bk 1 Oct. 114/1: Why does a Cannibal prefer an Irishman to boil down for soup? / Because he likes a broth of a boy.
1869		Lancaster Gaz. 21 Aug. 8/4: ‘A broth of a boy’ is a foolishly incomprehensible expression.
1876		Besant & Rice Son of a Vulcan III 200: You ought to have been a preacher and a boy. Faith, and a broth of a boy, and a broth of a preacher you’d have made!
1879		H. Hartigan Stray Leaves (2nd ser.) 194: [A] broth of a boy, who had plagued the adjutant, defied the sergeant-major, and had known every plank in the guard-bed.
1884		Ally Sloper’s Half Holiday 14 June 56: [caption] This is a Broth of a Boy, who has agreed to water the garden for sixpence, waiting to see if it’s going to rain.
1895		Truth (Sydney) 2 June 2/6: Agnes in her — ahem — breeks, looked a perfecct broth of a boy.
1901		Bulletin (Sydney) 12 Oct. 14/4: The histrionic knight of the lank, black locks is at heart (people say) a broth of a ‘white-headed boy.’.
1904		G.B. Shaw John Bull’s Other Island Act I: More power to your elbow! an may your shadda never be less! for youre the broth of a boy intirely.
1907		W.M. Raine Bucky O’Connor (1910) 187: Sure, you’re a broth of a lad.
1910		P.W. Joyce Eng. As We Speak It In Ireland.
1928		M. Bodenheim Georgie May 13: He was six feet high in his socks, the bigges’ broth of a boy yez ever laid eyes on.
1937		J. Tully Bruiser 196: He was a broth of a boy – weak as water and strong as a broken dam.
[1943		Kerouac letter Apr. in Charters I (1995) 56: Every one here is defeated, even this ‘broth of Breton.’].
1959		A. Sinclair Breaking of Bumbo (1961) 70: No, you’re a broth of a boyo, really.
1979		J. Morrow Confessions of Proinsias O’Toole 96: A broth of a bhoy, strong but merciful, articulate, humorous, tolerant.
1996		Irish Times 9 Nov. n.p.: Collins was more than just a broth-of-a-boy swashbuckler [BS].