What makes lasagne sauce taste sweet?

[mynameiswah]

When I make it it doesn't ever have that 'sweet' flavour I get in restaurants and bought lasagnes - what is it that they use? Marinara sauce or something? I've looked at recipes online and I just can't see anything specific... They usually just say tomato sauce.. and white sauce with milk.. is it the right combination of the two that creates that sweetness? Just curious!

Another nutmegger here.

But I add it to most mince dishes and cheesy sauces.

A little brown sugar and a balancing amount of balsamic or red wine vinegar, then a long simmer, gives that intense, partly sweet flavour.

Caramelising the toms by roasting also creates / concentrates the sugar that is in them.

It depends what you have time to do.

Onions are quite sweet when cooked.

My SIL makes the best lasagne I've ever eaten. She puts a splash of balsamic vinegar in when she sauteeing the onions at the start, then adds a tablespoon of raspberry jam (!) before simmering the sauce for at least 30 minutes.

Some conflicting advice, but a good ragu takes at least 2 hours to be acceptable.

Get it going, & walk away & stir occasionally.

The longer you cook it, the sweeter it will be. Adding some red peppers is nice. You can roast tomatoes and peppers first to add sweetness. But yes, sugar helps! :-)

@Owlsintowels
I've got a bottle of sherry which will never get drunk, will that do?

Maybe not the whole bottle though