No no no, you separate out the vegetation, if any, and keep it aside. Microwave any non-vegetable remainder for 15-30 seconds, depending on the mass of the burger: just enough to warm the meat. Transfer from microwave to toaster oven in two halves, toast briefly to crisp the buns, re-sizzle the meat, and melt the cheese. Arrange vegetation back in between. Enjoy a McDonald's burger that rivals its freshly served cousin. Finally, sit back and question the life decisions that lead you to putting this much thought into reheating fast food from McDonald's.