In a large nonstick skillet, melt butter over medium-high heat until sizzling. Stir in salt and pepper. Add chicken; cook 8 to 12 minutes or until juices are clear (turn once.) Remove from skillet; set aside. Reduce heat to medium. Stir flour into skillet. Add half and half and garlic, stirring constantly 1 minute or until slightly thickened. Stir in tomatoes and basil. Return chicken to skillet. Cook 4 to 5 minutes or until heated through. Garnish with basil leaves.