Slice squash in half, remove seeds, fill seed wells with chopped celery, onions, bell peppers, sprinkle with water and black pepper, then roast for about 45 minutes until squash is tender. For additional information see my Recipe #179443.
Steam broccoli (fresh or frozen) on stovetop in a saucepan with steaming insert.
While broccoli is cooking, remove skin from squash and puree in food processor. Discard skin. Place pureed squash in a 9x12" rectangular glass baking dish.
Once broccoli is cooked, stir in with squash, chopped onions, chopped celery, and fresh ground black pepper.
Slice 1 Roma tomato. Discard end slices. Place remaining slices across the top of squash mixture. Sprinkle with Mrs. Dash Seasoning Blend and pepper.
For an extra boost, sprinkle some red pepper flakes across the top. Bake at 350°F for about 30 to 40 minutes.