In A Large Skillet, Saute The Broccoli, Mushrooms And Onions In Butter Until Tender. Add Ham; Heat Through. Remove From The Heat And Keep Warm. In A Mixing Bowl, Beat The Eggs, Water, Mustard, Italian Seasoning And Garlic Salt Until Foamy. Stir In The Cheese, Tomatoes And Broccoli Mixture. Pour Into A Greased Shallow 1-1/2-Qt. Baking Dish. Bake At 375 Degrees F For 22-27 Minutes Or Until A Knife Inserted In The Center Comes Out Clean.