Lasagna

You will need:
Sauce -
200-400g ish of Mince meat of some sort (generally beef? but whatever really)
A jar or two of tomato pasta sauce, or tinned chopped tomatos, or a bunch of finely diced tomatos
A largish brown onion finely diced
Optional herbs/vegetables/garlic/whatever you want to add (grate the vegies, finely chop garlic)

Bechamel -
Butter
Flour
Milk
Optional cheese

The rest -
Lasagna sheets, from the shops or homemade.
Cheese

Fry the onion and garlic (if you're using it) in some oil over medium heat. Once soft add mince and fry until all browned and cooked. Add the vegetables if you want to, and then the tomatos or tomato sauce or the canned tomatos and let simmer for a while. Stir occasionally.

Once the sauce is simmering, melt about 2-3 tbsps of butter in a saucepan, put the heat low and then add 1/4-1/3 cup of PLAIN flour, stir well and make sure there are no lumps, don't stop stirring and let it slightly brown to cook out the flour. Then add about 1/2-3/4-1 cup milk, I usually add maybe 1/4 cup and then mix it all in and then add the rest. I don't know why I do it that way, and I don't think its necessary or makes any difference at all. Keep stirring it over low heat until it thickens, then take it off the heat. I usually add some cheese to it as well.

To assemble your lasanga:
I think traditionally you put bechamel on the bottom, but I don't like too much of it so I don't. If you want to, maybe make more bechamel or there won't be enough..
I do it like this: Meat sauce, lasagna sheets (fit as many in the tray whole as you can and then break bits up to fill in gaps), meat sauce, lasagna sheets, meat sauce ..until theres no sauce left. Then put some bechamel on the top, spread it out a little, then top with cheese.
Bake at about 180 for 15 or so minutes until the top is browned and delicious.