Directions

1. In a saucepan, bring broccoli and 1 in. of water to a boil. Reduce heat; cover and simmer for 3-4 minutes or until crisp-tender. Drain and set aside. Cut a 1/2-in. slice off the top of each tomato; with a spoon or melon baller, hollow out each tomato, leaving a 1/2-in. shell. Discard pulp. Sprinkle 1/4 teaspoon lemon juice into each tomato; place upside down on paper towel for 10 minutes to drain.
2. Meanwhile, in a skillet, saute onion in butter until tender. In a bowl, combine the flour, milk and broth until smooth. Stir into onion mixture. Bring to a boil; cook and stir for 2 minutes or until thickened. Remove from the heat; stir in Parmesan cheese, basil, salt, pepper and reserved broccoli. In a mixing bowl, beat the egg white until stiff peaks form. Fold into broccoli mixture.
3. Place the tomatoes in an ungreased 8-in. square baking dish. Spoon the broccoli mixture into each tomato, mounding in the center. Bake, uncovered, at 350 degrees F for 30-35 minutes or until a knife inserted near the center comes out clean and the tops are golden brown.