Flatten chicken to 1/4 inch thickness. Press lemon-pepper seasoning evenly on both sides. In large frypan, place oil and heat to medium temp. Add chicken and cook, turning once about 7 minutes or until fork can be inserted in chicken with ease. Remove chicken to warm serving platter; keep warm. In medium bowl, mix together vinegar, broth and garlic; add to frypan. Cook over medium-high, scraping up brown meat bits, about 2 minutes or until mixture is reduced and syrupy. Add butter; stir to melt. Place chicken on serving dish and spoon sauce over chicken. Garnish with parsley and tomatoes.