In unbaked pastry shell layer dabs of the cream cheese, onion, tomato, jalapeno peppers, shredded cheddar cheese, and salt and pepper. In small bowl, combine eggs and sour cream and beat well. Pour egg mixture into pie shell. Cover edges of pie shell with strips of foil to prevent excessive browning and bake quiche at 450 degrees for 30 minutes or until filling is set. Let quiche set about 10 minutes before cutting.