Heat oven to 350 degrees F. Line 15x10x1-inch pan with parchment paper, with ends extending over shortest sides of pan. Spray with cooking spray. Beat eggs, milk and flour in large bowl with whisk until well blended. Stir in next 4 ingredients; pour into prepared pan. Bake 14 to 16 min. or until edges are almost set. Top with cheese; bake 2 min. or until melted. Roll up omelette immediately, starting at one short end and peeling off paper as omelette is rolled. Place on platter; cut into slices. Serve with salsa.