1Heat oven to 350°F. In ungreased 2-quart microwavable casserole, mix chicken, bell pepper, tomatoes, 1 tablespoon Bisquick mix, the salt and pepper. Cover with microwavable plastic wrap. Microwave on High 3 to 4 minutes or until bubbly.
2In small bowl, stir 3/4 cup Bisquick mix, 1/2 cup of the cheese, the milk, egg and pesto until well blended. Drop mixture by small spoonfuls over chicken mixture. Sprinkle with remaining 1/2 cup cheese.
3Bake uncovered 25 minutes or until cheese begins to turn golden brown.