For tuna sauce
1. saute onion and garlic in butter. Stir in tomato soup and cornflour that has been mixed in 1/4 pint of cold water to make a paste. Add herbs, parslet and drained tuna.
2. For white sauce
Grate opion and saute in butter with mushrooms. Boil of liquid and then add flour and stir over heat. Slowly, while stirring, add the milk. Add cream and when smooth, add grated cheese and seasoning.
For the finished dish.
3. Boil the lasgne in salted water with a drop of oil until tender and then drain and dry on a cloth.
4. Butter a caserole dish and alternate layers tuna sauce, lasgne and white sauce.
5. Cover with foil and bake in 180C / 350F gas no.4 until piping hot