Preheat oven to 350 degrees F.
Place dressing mix in a large bowl. Saute onions and celery in reserved sun dried tomato oil. Add to dressing mix. Toss lightly. Stir in sun dried tomatoes, almonds and olives. Pour broth over mixture and blend lightly. Pack tightly into an aluminum foil-lined buttered 9x5x3 loaf pan. Cover tightly with foil. Bake in preheated oven at 350 degrees F. for 30 minutes.
Remove from oven to a rack. When cool, remove loaf from pan. Carefully peel off the foil. Line a cookie sheet with foil and lightly oil. With a sharp knife, cut into 1" slices. Place slices on prepared sheet. Broil until top is crusty and golden - about two to three minutes, watching carefully. Serve topped with slices of tomato and mustard as an open face "sandwich."