Preheat oven to 400° + line a baking sheet with foil

Wipe 2 mushrooms with a damp paper towel, remove stems + using a spoon, scoop out the dark gills; place on sheet pan bottom-side up, season with salt/pep + drizzle with oil; bake 10 min

Meanwhile, heat lightly oiled skillet over medium; season burgers with salt/pep, fave seasoning + cook 3 min per side til crispy

Divide burgers between mushrooms; add ¼ cup sauce + 2-4 tbsp cheese onto each, then bake 10-12 min until cheese is melted