How to Use a Microwave Oven

Microwave 101

px photography/The Image Bank/Getty Images

The microwave oven is now an essential part of most kitchens. During the summer or other hot times of the year, it's an excellent appliance to use because it won't heat up your kitchen the way an oven will. Unfortunately, most people still use the microwave to heat coffee, melt butter or make popcorn. That's just fine - but the appliance can do so much more! Read on to learn how to use a microwave oven.

How the Oven Works

The microwave works when the high voltage is converted to waves of electromagnetic energy, which is a combination of electrical and magnetic energy. This energy is in the frequency band of radio waves, not x-rays. A wave guide and stirrer blade work together to make sure the energy reaches all areas of the oven interior. When the door is opened or the timer reaches zero, the energy automatically stops, so no microwave radiation leaves the oven. All ovens also have two independent systems that ensure the electrical activity stops as soon as the door is opened.

The microwaves make the water molecules contained in food vibrate and 'wiggle', which produces heat. This is what cooks the food, and also why the oven itself doesn't heat up. That's why foods that have a lot of water, like fruits and vegetables, cook more quickly. Foods high in fat and sugar also cook more quickly.

Metal reflects the microwaves, and the energy passes through glass, plastic and paper. As soon as the microwave energy is absorbed by the food, it is converted to heat - so the microwave energy can't 'contaminate' the food.

Although heat is produced directly in the food, microwave energy doesn't cook food from the inside out.

More dense foods like meat are cooked primarily by conduction of heat from the outer layers, which are heated by microwaves.

In combination microwave/convention ovens, you'll notice that the interior is metal. A convection oven's special feature is a fan that constantly circulates hot air around the food, so it cooks more quickly and browns very evenly. Follow the cooking instructions to the letter if you have one of these appliances.

Never try to repair your own microwave. It is a complex appliance that includes a magnetron, high voltage transformer, thermal protectors, and complicated circuits.

Microwave Oven Safety

Now a few words about microwave safety:

  • The foods will be very hot when removed from the oven, so use oven pads and be careful.
  • If the food is covered during cooking, make sure to leave a small portion vented, or uncovered, so steam doesn't build up and burn you when the covering is removed.
  • The foods should sit as directed in the recipe after being removed from the oven so the heat can continue to spread and dissipate. This is called 'standing time', but it is actually more cooking time.
  • Most ovens have hot spots, and if you eat the food directly from the oven, a few areas could be superheated and will burn.
  • On the flip side, there can also be cold spots where the food doesn't get hot enough to kill bacteria. Follow stirring and rotating instructions carefully.
  • Don't use metal containers unless the recipe specifically directs you to: as stated above, microwaves bounce off metal, which can cause arcing and a fire inside the oven. Some recipes may call for shielding parts of the food, especially meats, with small amounts of foil. This is perfect acceptable as long as the directions are carefully followed.
  • Make sure any glass, plastic containers, and plastic wrap you use are labeled 'microwave safe'. You can also test containers, as directed on the next page.
  • Don't heat water or other liquids beyond the time recommended by the manufacturer or any recipe. Superheating can occur when plain water is heated in a clean cup for an excessive amount of time. The water will look innocuous, but when moved it can literally erupt out of the cup. Don't heat the water twice - that adds to the superheating risk. Adding sugar or coffee granules to the water will reduce the risk of superheating.
  • Never operate a microwave if the door is damaged or doesn't close securely.
  • Don't operate the oven while it is empty. This can also cause arcing and start a fire.
  • It's also a good idea to stand 3-4 feet away from the microwave when it is operating - just to be on the safe side!

Cooking Tips

The more you know about how to use a microwave oven, the better the results. These cooking tips are invaluable.

  • When using the microwave to defrost meat, the foods must be completely cooked right away. The microwave may have partially cooked part of the meat, and bacteria may grow if the food isn't thoroughly cooked.
  • Arrange food evenly in the pans and follow directions for stirring, rotating and standing time. Most recipes are developed for use in a 700 watt oven.
  • Check the food at the shortest time in the specified cooking range. Let the food stand as directed, then test using an instant read thermometer to be super safe, or test according to the recipe's doneness tests. You can easily cook it longer if the food isn't done.
  • If you're wondering if a dish you own is microwave safe, there's an easy way to test it. Place a cup full of water and the dish you want to test in the microwave. Cook at 100% power for one minute. If the water gets hot and the dish you're testing stays cool, it is safe to use in the microwave. If the dish gets hot, it contains lead or metals and shouldn't be used in the microwave.
  • Onions and other vegetables are easily sauteed in the microwave. Just chop as directed in the recipe, place in a safe container, add 1 Tbsp. of water and cook on HIGH for 1-2 minutes until soft. This is a great way to cook quickly with no added fat.
  • In general, the outside sections of the food will cook more quickly. So arrange fish fillets, for example, so the thinner parts are toward the center. When cooking on any other power level than HIGH, the oven cooks by cycling power on and off, so the energy has a chance to move through the food without overcooking. MEDIUM and LOW power are generally used to soften, melt, and defrost foods, while HIGH is usually used for cooking.
  • Follow the recipe! Remember to use microwave safe plastic wrap to cover the food while cooking if the recipe says to. Leave one corner uncovered to vent steam so it doesn't build up to dangerous levels. And always be careful when removing the cover from food; the steam will billow up quickly and it's easy to get burned. Pay careful attention to arranging the food, stirring, rotating, and standing instructions in the recipes.
  • To easily clean the microwave, place 2 Tbsp. of lemon juice in 1 cup of water in a 2 cup liquid measuring cup. Microwave on HIGH for 2-3 minutes, until the liquid is boiling. Let the liquid remain in the microwave, without opening the door, for 5 minutes. Remove the measuring cup. The microwave will easily wipe clean with a paper towel.

Get the Recipes!

These fabulous recipe are the last part in learning how to use a microwave oven. Enjoy every bite.

But first, do you know the wattage of your microwave oven? If you're not sure, here's an easy way to find out, according to the University of Tennessee. Fill a glass measuring cup with exactly one cup of lukewarm tap water. Microwave the water, uncovered, on HIGH until water begins to boil. If boiling occurs in less than three minutes, the wattage of your microwave is 600 to 700; three to four minutes, the wattage is 500 to 600; more than four minutes, the oven wattage is less than 500 watts. Most microwave recipes are developed for ovens with more than 600 watts of power. If your oven's wattage is less than that, you will probably need to add more cooking time.

Many of these recipes cook entirely in the microwave oven. Be sure to follow cooking, rotating, stirring, and standing times carefully. Never try to taste or eat food as soon as it comes out of the oven, because the food is still cooking and increasing in temperature.

Now enjoy these recipes!

Microwave Recipes

  • Microwave Meatloaf
    This classic meatloaf cooks to perfection in the microwave oven. I love the flavors and seasonings.
  • Microwave Salmon Pie
    Yes, you can cook a quiche in the microwave! There's a trick to the crust; rub it with spices or Worcestershire sauce to give it a brown color.
  • Microwave Peanut Brittle
    Peanut brittle is an excellent microwave recipe; it cooks much more quickly than making it on the top of the stove.
  • Microwave Shrimp Scampi
    Shrimp Scampi is one of my favorite meals. This easy recipe has the most fabulous garlic and lemon flavor.
  • Microwave Scrambled Eggs
    Light and fluffy scrambled eggs are easy to make when you use the microwave oven.
  • Microwave Tuna au Gratin
    For a super quick, kid friendly meal, this recipe is a winner.
  • Mexican Chicken
    This quick and easy recipe for two uses just five ingredients.
  • Curried Fish Fillets
    A simple curry sauce elevates this fish dish into another realm; it's that good!
  • Tomato and Cheese Fish Fillets
    Fish fillets cooked with tomatoes and topped with melted cheese is a healthy and simple dinner.
  • Red Snapper and Yellow Squash
    This colorful dish, which uses only five ingredients, is fresh and easy to make.
  • Easiest Fudge in the World
    Take two ingredients, add a few minutes and a microwave oven, and you have smooth, creamy fudge. Yum.
  • Microwave Meal Magic Recipes
    This collection is of recipes that cook entirely in the microwave oven.