Wash spinach thoroughly; remove and discard stems from spinach. Tear into bite-size pieces.
Coat a Dutch oven with cooking spray; place over medium heat until hot. Add spinach; cover and cook 3 minutes or until spinach wilts, stirring occasionally. Remove from heat, and stir in sesame seeds, lemon juice, and salt, tossing gently.
Tip: To toast sesame seeds, place them in a hot nonstick skillet over medium-high heat (no oil), and cook for 3 to 4 minutes, stirring constantly. Don't cook them much longer, or they'll burn.