Adam Stevens gave debuts to Ollie Luto, Matt Baker, Keegan Everington and Jack McMillan.
The Gingerbreads opened the scoring on 8 minutes. Lee Shaw put a cross along the six yard line and Spalding's Paul Walker turned the ball passed the goal keeper.
The lead was doubled on 16 minutes. Danny Meadows headed home a Curtis Burrows corner.
The controlled the rest of the half but couldn't and to their lead.
With the competition allowing 7 substitutions, Adam Stevens took full advantage in the second half. Rhys Lewis and Andy Wright came on for Keegan Everington and Jack McMillan.
With 20 minutes to go a triple substitution. George Couzens, Reece Thompson and Tom Potts came on for Jeremiah Dasalou, Lee Shaw and Ollie Ludo.
It was George Couzens who got The Gingerbreads through a cute finish passed the Spalding goal keeper.
Academy Scholar Tom Curtis and Charlie Wolfe came on for the final 15 minutes.
A late free kick from Spalding was the end of very little that troubled The Gingerbreads defence.
The winner of tomorrow's final quarter final between Gainsborough Trinity and Lincoln City will host The Gingerbreads in the semi final.
Updated 22:24 - 14 Jul 2017 by Simon Hayes