Divide the ground beef into 4 patties and season with salt and pepper.
In a large skillet, melt 3 tablespoons butter over medium-high heat.
Sear the burger patties for about 3 minutes per side until browned.
Set the burgers aside, then melt the rest of the butter in the pan.
Stir the truffle oil and shallots into the butter, then add the mushrooms.
Sauté the mushrooms for 8-10 minutes until they soften and release most of their liquid.
Stir in the garlic, then pour in the wine and de-glaze the pan.
Bring the sauce to a simmer and cook for 8-10 minutes to evaporate most of the wine.
Dissolve the beef bouillon in the hot water, then stir the mixture into the pan.
Bring the sauce to a simmer again, then add the burger patties and cook them uncovered for about 15 minutes or until the sauce thickens and the meat is cooked through.
Top the patties with mushroom sauce and garnish with thyme, then serve.