As crazy as that might sound to hear, a traditional Northern Italian lasagna isn't stuffed with ricotta, and it doesn't come topped with a layer of melted mozzarella either. The work that falls to ricotta in many recipes - providing the creamy layers in the filling - is instead accomplished with a silky bechamel sauce in a traditional lasagna. For those not familiar, bechamel is one of French cuisine's five mother sauces, a simple sauce made with butter, flour, milk, and seasonings.
Lasagna is, by no means, flavorless, even in the most simple recipes. Amping up the richness won't always work when you try to revamp it. What you need instead is the lemon's contrasting brightness and the way its acidic edge slices right through all the heaviness. One ingredient after another, it lifts the entire dish from within. The tangy cheese finds a companion in the sparkling zest, one that balances out its rough edges.
Besides adding an extra boost of nutrients, spinach can add a really grounding, earthy flavor to a ricotta mixture or veggie layer. The one step that you can't miss when adding spinach to your lasagna, though, is to cook it first. The types of spinach commonly used for lasagna, including curly or flat-leaf, contain a lot of water. If you fail to cook out that water beforehand, the residual moisture may permeate the other layers, leading to a watery, heavy, and soggy pasta dish.
You could make a strong case that lasagna is the most popular Italian dish ever, or at least in head-to-head competition with spaghetti. It's versatile, beloved, and easy to experiment with, so there's no reason not to play with the recipe. It's a great canvas for exploring new flavors. For that reason, if you're looking for an unexpected umami twist, try making your next lasagna with some miso.