Thoroughly rinse the mushrooms under cool water, pat dry, and slice them evenly about a quarter-inch thick.

Pour 2 tablespoons of olive oil into a large skillet over medium heat and let it heat until shimmering.

Add sliced mushrooms to the hot skillet in a single layer and cook undisturbed for 3-4 minutes until golden brown.

After browning, stir occasionally and cook for an additional 5-7 minutes until deeply browned and tender.

Add minced garlic and sauté for 1-2 minutes until aromatic, stirring constantly.

Gradually add fresh spinach, tossing gently, and cook for 2-3 minutes until wilted.

Season with salt and pepper, and squeeze in the juice of half a lemon, stirring to combine.

Remove from heat and serve immediately while hot.