First, preheat the oven to 200 degrees so that it is already hot when you have finished preparing all the ingredients. To make your crepes:
First sieve the flour into a bowl then add the eggs and stir in the milk a little at a time using a whisk.
Then lightly grease a medium frying pan and when hot, pour in a ladle of batter sufficient to cover the bottom. These cook in a few seconds so turn the crepe to cook on the other side and place on a warm plate. Prepare twenty crepes.
Next, chop the onion, bay leaf and sage and fry in a pan with a tablespoon of oil.
Add the ground beef and brown it in this chopped aromatic mix for a few minutes so that flavour is infused into the meat. Season with salt and pepper and pour in a glass of white wine until it evaporates.
Then add the tomato puree with a few spoonfuls of stock cover and cook over a low heat for 45-50 minutes.
Meanwhile, prepare the béchamel sauce:
Melt the butter in a thick-bottomed saucepan, add the sifted flour and mix well whilst heating it for two or three minutes.
Then slowly add the hot milk, stirring constantly so no lumps are formed. Keep the flame very low and simmer the sauce for about ten minutes.
Then add salt, pepper and sprinkle with nutmeg.
To assemble this dish, layer the crepes in a buttered round baking tin, alternating with a layer of meat sauce and a béchamel sauce. Finish with the béchamel sauce on the top layer and sprinkle with grated parmesan and a few knobs of butter. Place in a hot oven for thirty minutes grilling for the last 10 minutes to create a nice golden crust.