Ashwell Prince became the first Lancashire batsman in 16 seasons to score a century in each innings of a match as the visitors turned the screw on day three against Kent in Cantebury.
Already promoted as unbeaten Division Two champions, Lancashire declared their second innings on 393-5 before Kent reached stumps on 32-1, a total deficit of 417 runs.
Kent had already lost veteran opener and first-innings top-scorer Rob Key to a fractured left thumb when fielding in the gully earlier in the day, emergency opener Daniel Bell-Drummond (8) was dismissed before the close.
Lancashire openers Paul Horton and Luis Reece had earlier resumed on 75-0 without loss and took their partnership through to three figures inside 45 minutes before Reece departed for 47.
Visiting skipper Horton sneaked a sharp single to mid-on to reach a patient half-century from 145 balls and with six fours as he and Prince battled through to a lunch total of 140-1.
The second-wicket pair upped their tempo after the interval as Prince recorded a 107-ball fifty with three fours and a six, while Horton went on to post his third hundred of the LV= County Championship season.
But his innings came to an end when, with his score on 106, he edged an attempted dab down to third man off Darren Stevens into the hands of James Tredwell at slip.
Karl Brown (14) then raced down the pitch to Tredwell only to slice an aerial drive high to Matt Hunn at mid-off, and Luke Procter (18) heaved across the line to go lbw to Stevens.
But Prince batted on to become the first Lancashire batsman since John Crawley at Colwyn Bay in 1998 to hit hundreds in both innings of a match with a rasping off drive against Tredwell.
Soon after, he cut hard at a short one from teenage debutant Hunn but found a thick edge to be superbly caught behind by Sam Billings for 108.
Andrea Agathangelou (51 not out) marched in to smash three fours and two sixes in a 35-ball half-century against a tiring Kent attack to spark the declaration late in the day.