An attritional third day at Trent Bridge saw Matthew Montgomery take centre stage, building on his day one century gaining 177 runs off 318 balls under blue skies and glorious summer sun.
Notts finished their first innings on 442 all out, with useful contributions from Montgomery and Calvin Harrison.
Lyndon James took the only Nottinghamshire wicket of the day, as Essex ended the evening at 199/1, a lead of 55 thanks in part to Sir Alastair Cook’s 122nd first-class half-century.
Notts managed to build on their total of 326/5 entering the third day at Trent Bridge, with Matthew Montgomery and Liam Patterson-White opening the day’s play after a late Steven Mullaney dismissal in the final over of day two.
Patterson-White gained 12 runs early on, but clipped a Porter delivery off outside edge, which was caught by Harmer.
Montgomery meanwhile surpassed 150 off of 287 balls, stroking his 23rd four beyond the boundary.
Debutant Calvin Harrison partnered the 23-year-old and made a captivating 31, including seven boundaries, but was clean-bowled by Doug Bracewell.
Hutton entered the field, but after hitting an early maximum, sent Harmer’s delivery skyward, with Shane Snater underneath it to claim Essex’s third wicket of the day.
It was Montgomery who remained the pick of the bunch, coping fabulously with 317 balls across the innings but fell one short of his career-best total when he was trapped for lbw off of Critchley’s bowl, ending his batting stint with a score of 177, but leaving the field to a standing ovation from all sides of Trent Bridge.
Dane Paterson entered play as the final batter, but could only manage one run as he lofted Critchley’s delivery towards Westley, who made the catch to see Nottinghamshire end their first innings all out for 442 at lunch.
Essex emerged with Nick Browne and Sir Alastair Cook after lunch trailing by 144 runs, requiring a strong second innings to put the Notts batting order under pressure.
They began their chase strongly, battling through the first 26 overs without loss until Lyndon James rapped Nick Browne’s front pad to dismiss the opener for 27.
Tom Westley replaced Browne, and scored an unbeaten 16 to see Essex into Tea at 85/1, with Cook on 32*.
And it was Cook and Westley who forged a formidable partnership with both batsmen claiming their half centuries - Cook in 133 balls, with a boundary off of Patterson-White’s delivery, and an hour later, Westley managing the same feat, surpassing 50 in 102 balls.
Essex finished the day 199/1 with Cook (87*) and Westley (70*) forming a stubborn partnership (137).