Rinse spinach under cold water and drain well
Remove tough stems if desired
Pat spinach dry so it sautés instead of steaming
Heat a skillet over medium-high heat
Add 1–2 tablespoons olive oil or butter
Add 1–2 minced garlic cloves (optional) and sauté 15–30 seconds until fragrant
Add spinach in batches if needed
Toss frequently until wilted, 1–3 minutes
Season with salt and black pepper to taste
Add a squeeze of lemon juice or a splash of vinegar (optional)
Stir to combine and serve immediately