Tricolor Penne

Heat covered 6-quart pot of water to boiling on high. Add 2 teaspoons salt. Cut tomatoes in half and cut chicken into 1/2-inch chunks. In 12-inch skillet, heat 1 tablespoon oil on medium-high until hot. Sprinkle chicken with 1/4 teaspoon salt and 1/4 teaspoon freshly ground black pepper. Add chicken to skillet in single layer; cook 4 minutes or until golden on both sides, stirring once halfway through. With slotted spoon, transfer to plate. To same skillet, add tomatoes and 1/8 teaspoon salt. Cook 3 to 4 minutes or until tomatoes are soft, scraping up browned bits; stir chicken and any juices on plate into skillet and remove from heat. Meanwhile, add pasta to boiling water in pot. Cook as label directs, stirring occasionally. Reserve 1/4 cup pasta cooking water. Drain pasta and return to pot, along with tomato mixture. In blender, puree arugula, Parmesan, garlic, reserved pasta cooking water, 1/4 teaspoon salt, and remaining 1/4 cup oil until smooth. To pot, add arugula mixture, stirring until well combined. To serve, sprinkle with additional grated Parmesan, if you like.