The Rhinos were electric from the start, crossing twice in the opening five minutes. Winger Fran Goldthorp opened the scoring and player of the match, Gaines, doubled the lead, grabbing her first of the match off the back of more hard drives from Leeds forwards. Courtney Hill converted to give Leeds a 12-0 lead.
Loose-forward Lacey threw the ball over the top once more to her captain Hill, who beat three defenders to score next, under the posts.
Ellie Oldroyd came off the bench to score her first of 2019, Gaines converting to make it 24-0 and on half-time Lacey put Chloe Kerrigan over with Gaines again adding the extras for 30-0.
Second-half tries for Laverick, Gaines (2), and Beevers with Gaines adding conversion points sealed the plus-half-century win for Leeds.
Elsewhere, Castleford Tigers proved far too strong for visitors Wigan Warriors; the hosts won comfortably 56-9. But it was far from plain sailing for home side Wakefield Trinity who were out-gunned 20-4 by York City Knights.
And in the remaining fixture, Bradford Bulls went down 34-18 at home to St Helens.