Carefully remove tray from oven. Push vegetables to middle. Tray will be hot! Use a utensil.
Combine ¼ cup water, demi-glace, and cornstarch in a mixing bowl.
In another mixing bowl, combine ground beef, panko, Parmesan, and a pinch of salt and pepper. Form ground beef mixture into eight equally-sized meatballs.
Pour demi-water mixture into tray. Place meatballs around outside edge of tray.
[PIC: veg in middle stuff on side]