What should I do with a just-baked lasanga?
The lasanga will be even better 4 hours from now, but you definitely need to get it cold. Bacteria grow between 40&deg;F and 140&deg;F (often called the "danger zone"), so you need to get it cold now. I wouldn't put hot lasagna directly into the fridge, though, as it will raise the temperature of your fridge. Let it cool for a little while, maybe even let it sit on some ice, then refrigerate.

You can re-heat it all at once, in a low temperature (250&deg;F or so) oven, or cut into individual servings and microwave it.