I'm doing some freezer batch cooking for a friend recently out of hospital and one of the requested dishes is lasagne. I've made the ragu and bought - to save time, some no pre-cook lasagne sheets and ready- made bechamel. So what do I do? Do I layer it up cold and - apart from the ragu -uncooked ready for the freezer? Or do I cook it and give instructions that it is just heated through when taken out of the freezer? And should it be thawed before cooking? Very grateful for any help.