The Puritans beat Brackley Town Saints 3-1 after extra-time in Tuesday’s final at Buckingham Athletic.
Extra-time goals from Felipe Barcelos and substitute Ricky Johnson saw United come from behind to lift the cup. Earlier it had taken a stoppage-time equaliser from Johnson to cancel out Lewis Baldwin’s opener.
Saints had the better of the opening period but United twice went close through Louis Joyce and Leam Howards who was denied by keeper Dan Farrell.
It was Saints who broke the deadlock in the 37th minute when Matt Hammond was upended just inside the area and Baldwin converted the ensuing spot-kick.
United’s best chance after the restart saw Johnson and Ollie Stanbridge fail to convert from close range. But three minutes into stoppage-time Johnson surged into the area to beat Farrell.
United finally took the lead in the 111th minute. Stanbridge raced down the right and his cross found Barcelos who nodded the ball home.
Five minutes from time Johnson made it safe when he got on to the end of a through ball before slotting home from12 yards.