Juicy Gourmet Burger Sliders

Preheat an outdoor grill for medium-high heat and lightly oil the grate.

Stir mushrooms, shallots, garlic, thyme, salt, and pepper together in a bowl. Heat olive oil in a skillet over medium heat;cook and stir mushroom mixture until golden, about 8 minutes. Pour red wine into skillet; simmer until liquid evaporates, stirring slowly, about 2 minutes. Spread mushroom mixture onto a plate to cool to room temperature, about 5 minutes.

Crumble ground chuck into a bowl; pour truffle oil over beef and massage oil gently into beef until evenly distributed. Fold mushroom mixture into beef mixture until combined; form 6 patties approximately the size of baguette slices.

Grill patties until no longer pink in the center, about 3 minutes per side. An instant-read thermometer inserted into the center should read at least 160 degrees F (70 degrees C).

Toast baguette slices until crisp and golden. Place each patty on a baguette slice, top with 2 shaved slices of Parmesan cheese, about 1/4 cup arugula, and a second baguette slice. Secure each slider with a toothpick.