Add oil to a large heavy based pan, heat
Finely dice onion, add to the oil, sauté until soft
Add garlic, sauté for further 2 mins,
Add mince and cook until brown
Once mince has browned add the tomato passata
Rinse and drain the lentils, add to the pan with the grated carrots and zucchini
Add the mixed herbs of choice.
Simmer uncovered for 20mins, watch the mix, you may need to add 1-2 cups of water to allow the lentils to soften, as they will absorb moisture from the sauce while cooking. I find it better to add the water as needed, so that you don't end up with a really sloppy mixture at the end.
While the meat sauce is simmering, roughly chop the cauliflower, steam until tender then purée, I usually use a stick blender for the cauliflower
Now to make the bechamel sauce, start by warming the milk, you can do this in the microwave if you wish.
In a saucepan heat 3 tbs olive oil, add the flour and cook for 2 mins
Gradually add the warm milk mixing continuously, you will end up with a smooth thick sauce, add the grated cheese. Once melted through, stir in the cauliflower purée
Finish off the meat sauce by seasoning as desired.
Now to layer the meat sauce, white sauce and lasagne. Start with a single layer of meat sauce, top with pasta, then a single layer of white sauce, top with pasta again, and repeat, (Meat, pasta, white sauce, pasta). Keep going until everything is used up. You can finish on a meat sauce or white sauce layer as the top, it's up to you!
Sprinkle the top layer with a little extra cheese
Bake for 30 mins in the oven at 180 degrees Celsius
Allow to cool a little before you slice and serve, it holds together a little better once it has all stopped bubbling