Remove stems from 2 mushrooms + scoop out the dark gills with a spoon, then rinse + pat dry; heat 1 tbsp oil in skillet over med-high + cook mushrooms 2-3 min per side until browned + tender; add salt/pep + set aside

Form bison into 2 thin patties; heat 1 tbsp oil in skillet over med-high, season with salt/pep + cook 3-4 min on one side; flip over, add 2 tbsp mozzarella to each burger + cook 3-4 more min (remember meat keeps cooking after being removed from heat, be sure not to overcook for best results)

Add mushrooms to plates, top each with a burger + a handful of spinach—yuum!