Heat A Large Skillet Over High Heat. Sear The Pork Chops Until Browned, 1 To 2 Minutes Per Side. Transfer The Pork Chops To A Slow Cooker. Mix The Brown Sugar, Ketchup, Onion, And Lemon Juice In A Bowl; Spoon Over The Pork Chops. Cook On Low Until The Pork Chops Are Very Tender, 4 To 6 Hours.