Preheat the oven to 300°F.
Season the medallions liberally with salt, pepper, and ground bay leaves. Let sit at room temperature for 10-15 minutes.
Set a 10-inch skillet over medium-high heat; when hot, add 1 1/2 tablespoons of the butter and swirl the pan. Add the medallions and sear on the top and bottom until nicely browned—about 2 minutes per side. Using tongs, sear the edges until a little browned. Return the medallions to either their top or bottom and place in the oven for 5-6 minutes, or until done to your liking. Remove from the oven and transfer medallions to a warmed plate; tent to keep warm as they rest.
Return the skillet to the stovetop (medium-high) and add remaining butter and the jelly. When the jelly is melted, deglaze the pan with the red wine. Cook until syrupy, adding more wine if necessary.
Slice the medallions and fan out each medallion on dinner plates. Spoon elderberry sauce over, add vegetables, and serve.