Tuna Melt Stuffed Portobello

Ingredients

• 2 large portobello mushrooms (stem removed)
• 6 oz. tuna
• 4 artichoke hearts, chopped – optional
• 1 stalk celery, finely chopped
• 2 tbsp. finely diced onion
• 1 oz wedge lite laughing cow cheese
• 2 tsp. dijon mustard
• 1 egg white
• salt and pepper to taste
• 2 thin slices swiss cheese
• 2 slices tomato