Combine first 8 ingredients in a small bowl; stir well.
Cover and chill thoroughly.
Combine lemon juice and sesame oil; brush mixture evenly over both sides of each fillet.
Place fillets in an 11 x7x1 1/2 -inch baking dish coated with cooking spray.
Bake, uncovered, at 450° for 15 minutes or until fish flakes easily when tested with a fork.
Transfer to a serving platter.
Spoon tomatillo mixture evenly over fillets.