Brush slices of bread with dressing. Place slices on baking sheet. Bake under broiler for a few minutes or until lightly browned (watch carefully). Heat oven to 350. Line bottom and sides of a 10 inch springform pan with bread slices, cutting to fit, and allowing bread to come 2 inches up the sides.
Blend mayonaise and flour in medium saucepan. Whisk in milk. Cook, stirring, over medium heat until sauce comes to a boil and thickens. Remove from heat; stir in parmesan cheese.
Combine cooked linguine with eggs, 1 cup swiss cheese, green onions and cheese sauce.
Pour into prepared crust.
Arrange tomatoes on tart.
Sprinkle with remaining swiss cheese.
Bake 25 minutes. Let stand 5 minutes before serving.