How is this lasagna pasta supposed to be cooked? I will try to do lasagna and I have doubts about how to deal with the pasta. The bolognese and bechamel sauces are fine (at least I know how to approach them).
The problem I am having is with these &quot;pre-cooked&quot; lasagna pasta sheets (this is in France, Barilla is a very common brand of pasta over here)

Instead of a written description of how to use them, they only went for a few icons:

What does the first icon mean?
It could be a part of the bechamel sauce recipe, but it misses everything else (the roux, etc.).
Am I supposed to boil 0.9L of milk, pour it in the flat bowl, then put the sauce (I cannot believe that, maybe a first layer of pasta on top of the milk? - still does not make a lot of sense) and then the layers of bechamel and sauce?
In other words: where does this 0.9L of milk go?
EDIT: on The French Barilla site they have a section with recipes, including a few lasagnas using the pasta I have. https://www.barilla.com/fr-fr/recettes/collezione/lasagnes-a-la-sauce-napoletana-et-legumes-grilles for instance mentions milk only in the context of the bechamel sauce.
FINAL EDIT: I got a message from Barilla telling me that the first icon is &quot;the recipe for bechamel&quot;... Well never mind. I had the bolognese sauce done my own way and I used a 50 g flour + 50 g butter (roux), + 0,9L milk and the texture &amp; amount was perfect. Thanks everyone.
Barilla say their lasagne is no-cook (not all lasagne is), so I can only assume they expect you to make your béchamel with 900ml milk, then use a jar of their bolognese sauce in the alternate layers. It's a tad lacking in precision, for sure.
Personally, i'd just search a no-cook lasagne recipe online, as the liquid balance is pretty important for lasagne - too much &amp; it's like soup &amp; slime, too little &amp; it's a brick.
I just checked Barilla sites &amp; recipes around the world, most Barilla is no pre-cook - it also says that on your box - only their wavy lasagne is pre-cook.