I've never frozen canned mushrooms, but this method works on many similar foods: You'll need something flat that will fit in the freezer compartment (short term). I usually use a cookie sheet. You might also use a plastic plate or even a piece of stiff cardboard. Cover the cookie sheet with waxed paper (if you don't have any, you could try aluminum foil). Drain the can. Place the mushrooms in a single layer on the waxed paper, not touching. When frozen, place the mushrooms in a freezer bag. If you don't want to lose the liquid in the can, freeze them in ice cube trays. Then store in a freezer bag.

Oh Suzieque, this looks like it requires a visit to the CICU immediately after eating, but wow, does this sound fabulous. Thanks for the recipe, I have copied and saved it for sometime soon when I'm feeling indulgent! Its a special occasion dish. I had some guests a few weeks ago who would have loved this, I'll be sure to make it for their next visit! (Instead we had cheeseburger soup which is pretty decadent as well.)

I'd put some stiff plastic or parchment wrapped cardboard, along the cut sides and top. Or maybe freeze partway first and use plastic wrap. Remove before thawing. The more air you keep out, the better it will be. The issue with the crust is that you can't heat it to toast it back up. If it's not nice when thawed, you can always reimagine it, like maybe break it up into a parfait or trifle.

If i have a 1/4 pint of a similar sauce leftover from a meal, i do not hesitate to freezer for another meal. If i'm prepping garden harvest for the freezer i leave out any dairy so i have options later. I have a dozen+ sauces and soups for the Fall/Winter and like to make and some have small or more dairy that i add before serving. Stired in off the heat or blendered for a bisque. It is easier to reheat a sauce without the dairy. No need to watch it like a hawk. I have a small dairy drawer in my freezer. Cheeses, parm rinds, yogurt, butter, cream cheese, heavy cream, ricotta, sour cream, etc. Like mentioned, re-heating a sauce with dairy it needs to be tended carefully to not hit above a boil. Without dairy it can be left alone a bit. Roasted peppers, garlic, tomatoes, stocks...flat packed separately can become many dishes. I'm making a roasted corn/veg/tomato chowder this week. Easy with so many choices. If you have a favorite recipe, make it to the point before adding dairy. Then freeze. Add your dairy fresh, or freeze 1/4 pints of dairy to add, once thawed, as the recipe states...usually at the end of cooking off the heat. I've been roasting for weeks now when i have time. Usually when the oven is on for something else---sharing the heat. We have a few favorites like Leek, veg, garlic, potato soup. Veg/tomato soup. A few pasta dishes. I just roast, then pulse in my food processor a bit chunky that also give me options to later puree, or leave a bit chunky for a salsa...adding something fresh like lime, cilantro, red onion, etc.