1. Make red sauce by braising onion in oil till softened. Add tomatoes and spices and cook till oil comes to surface. Leave aside.
2. In a pot heat oil for mince. Braise onion till softened. Add masala, spices and vinegar and washed & drained mince. Cook till done. Leave aside.
3. Preheat oven to 180degC.
4. Grease an oven proof dish. Leave aside.
5. Heat butter for white sauce. Whisk in flour till smooth. Add milk and bring to boil, continuously whisking for a smooth sauce. When thickened remove from heat. Season with salt and pepper.
6. Spoon some white sauce into oven dish.
7. Place flat few lasagna sheets.
8. Spoon on some white sauce, then mince, then red sauce. Cover with lasagna sheets.
9. Repeat 1 or 2 more layers, depending on size of dish used. I usually make 3 layers.
10. Sprinkle cheese on white sauce.
11. Sprinkle dried herbs.
12. Cover with foil.
13. Place in preheated oven and bake for 45min.
14. Remove from oven and leave to rest for 10-15min.