Light Tuna Salad

In a bowl, mix the iceberg lettuce, tomatoes, green pepper, corn and onion slices together.

Flake the tuna and add to the bowl. Sprinkle the olives over the salad and mix all the ingredients well.

To prepare the dressing, add the mustard and the mayonnaise. Pour in the lemon juice and mix well. Then add the oil and mix well. Season with oregano and salt. If needed, you can dilute with some water.

To serve, pour the sauce over the salad and toss.