Denise's Vegetarian Lasagne

This recipe is one from Denise's family, is a great meal for impressing people with, and it gets rid of all those limp carrots and other vegetables sitting in the bottom of the fridge.
Our recipe involves the wonderful help of a food processor, but if you have the time and a sharp knife, chop away.
I'm a near-enough cook. I don't believe in measurements, that near enough will still turn out okay. These quantities can be changed, if you like more garlic, or no garlic, or if your tomato sauce doesn't have enough tomatoes in it, add more. However try to stick the the quantities for the Bechamel Sauce otherwise you'll have thick or very runny cheese sauce.

Vegetable Sauce
Process 1 onion. Saute onion in large saucepan with oil and garlic (1 crushed clove or 1 tspn of minced) until cooked. Turn down the heat so it doesn't burn.
Use any vegetables you want: maybe 3 potatoes, 2 carrots, ½ sweet potato, 1 capsicum, broccoli, basically anything in the fridge. Leafy things such as spinach can be roughly chopped or ripped and added later.
Put the vegetables in a food processor until minced, add to onion mixture.
Add sliced mushroom, peas and corn if you wish.
Simmer on the stove with 1 large can of tomatoes, parsley, basil, any other herbs, and leafy vegetables, stirring often.
The mixture is cooked when the vegetables are soft and not starchy.
The best test would be if you are happy eating it in its own right as a pasta sauce.

Bechamel Sauce
Melt 1½ tablespoons of butter in smaller saucepan over low heat.
Add 3 tablespoons flour, cook 1 minute.
Add 1 cup milk, stir continuously, making sure to blend the butter/flour mixture into the milk so that it is not lumpy.
When the milk mixture is thick, turn heat off but leave on stove.
Mix in grated cheese (mozzarella is preferable but tasty is good too).

Constructing the Lasagne
Put one layer of lasagne noodles in the pan. Put vegetable sauce in a layer on top of it.
Put another layer of lasagne noodles in the pan. Put bechamel sauce on top of that.
Put another layer of lasagne noodles in the pan. Top with more grated cheese.
Bake for 30 minutes in the oven, 180 degrees.
Remove lasagne, top with a mixture of cream and parmesan cheese (usually one small 300ml carton of cream is adequate, parmesan mixed in so that it is plentiful, but so that it will all blend in). Bake for another 15 minutes in the oven, 180 degrees.

Eat!!!
(it tastes even better the second day, if there's any left)

A disgusting variation we tried once, omit the vegetable sauce, and make layers of cheese sauce and lasagne sheets. Oh decadentent!