Prep Station → Slice mushrooms, garlic paper-thin, zest lemon—set pasta water to boil with salt.

Mushroom Sear → Heat 1 tbsp oil in large skillet high; add mushrooms in one layer—cook 5 minutes until golden.

Garlic Bloom → Lower to medium-low; push mushrooms aside, add remaining oil and garlic—cook 2 minutes until golden.

Chili Heat → Sprinkle chili flakes into oil; let sizzle 30 seconds—fragrant base ready.

Pasta Timing → Drop spaghetti in boiling water; cook 1 minute shy—reserve 1 cup starchy water.

Spinach Wilting → Toss spinach into skillet off-heat; residual warmth collapses leaves perfectly.

Emulsion Magic → Add ½ cup pasta water to skillet; return to medium—stir vigorously to emulsify.

Pasta Union → Drain spaghetti; add to skillet with lemon zest/juice—toss until glossy.

Season Perfect → Taste and adjust salt, pepper, chili—sauce should cling lightly.

Fresh Finish → Plate with parsley and optional Parmesan—serve with extra chili flakes.