I’m a huge casserole fan. Beef, Broccoli & Potato Hotdish is my favorite. (Hotdish is the Minnesotan name for casserole.) In my early “casseroling” days, I would just toss together ingredients that I thought would taste good together in a 9-by-13 inch pan and bake them. It was easy and the results usually tasted good, but there were always some minor imperfections. Depending on the ingredients, sometimes the casseroles came out watery. Other times, some ingredients were overcooked and mushy while some had a little too much bite.
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Since I test recipes for a living as an associate food editor at EatingWell Magazine, ending up with something less than perfect became rather irritating, so I had to change my method. Now I’ve perfected my favorite casserole and can use what I’ve learned to make others flawlessly too. Here are the secrets I’ve discovered to making perfect casseroles:
1. Remove extra moisture from wet vegetables before cooking.
If you don’t want to end up with a swimming pool at the bottom of your casserole, you may have to give certain vegetables some TLC before they hit the baking dish. Frozen vegetables can be particularly problematic. Thaw them in a strainer so they lose their extra liquid. You can squeeze moisture out of frozen greens like spinach to dry them out. Also be wary of mushrooms: they’re mostly water and need to be precooked.
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2. You may have to “par-cook” vegetables that take longer to finish.
“Par-cook” is chef speak for partially cooking something. If you want to mix and match ingredients that cook at different rates, you need to ensure that everything finishes at the same time. That’s where par-cooking comes into play. If you give ingredients that are slower to cook a head start—such as potatoes, carrots or other root vegetables—and then add them to a casserole that also has quicker-cooking veggies, such as broccoli or green beans, they’ll be finished around the same time. You can par-cook vegetables by steaming, boiling and even roasting. Just remember not to cook them all the way. They’ll finish cooking in the casserole. Find out the best way to cook 20 different vegetables here. 
3. Don’t cook pasta all the way through before using in a casserole.
This sort of goes along with secret #2, but I thought I would give it its own mention since pasta is a mainstay in casseroles (hello lasagna!) and getting the right texture can be tricky. Regular pasta doesn’t really have the chance to cook properly if you add it in its dry state to your casserole. And if you cook it all the way, it turns to mush. Cook your pasta up to 2-4 minutes shy of the suggested cooking time on the package. (Choose 4 minutes if you plan on freezing the casserole.) It should just be very “al dente” before you add it to the casserole, where it will finish cooking perfectly.
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4. Make sure your casserole is the right temperature before you bake it.
The beauty of casseroles is that you can freeze them and eat them another day. Unfortunately this can wreak havoc on your casserole if you don’t do it properly. Some folks just throw the casserole in the oven frozen and let it bake for longer, but this can lead to really overcooking your ingredients. Be sure to defrost your casserole completely in the refrigerator before you bake it. This can take up to 2 days. Also, let it come up to room temperature as your oven preheats. If you put a cold casserole in the oven, the outer edge could cook too fast while the middle cooks too slowly.
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Get the Recipe: Broccoli, Beef & Potato Hotdish 
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