Grim's Grub: Here's how military technology revolutionized cooking

And how Percy Spencer became famous, likely for the wrong reason.


In a Massachusetts Institute of Technology Raytheon lab, paid for by the U.S. Department of Defense, an engineer named Percy Spencer toiled with teams of experts in the field of power tubes - at that time the technological marvel that made things like radios work.

For some reason, Spencer isn't well-remembered as one of the lynchpin inventors to help the U.S. military maintain communications throughout World War II, but he was. The war may have been lost without him.

At the time, combat radar technology was dependent on technology called magnetrons, and Spencer was a key figure in developing a way to increase production at Raytheon from 100 magnetrons per day to 2,600. It was the second highest priority project during the war right behind the Manhattan Project.

Spencer's contribution earned him the Distinguished Public Service Award.

Though he's not well-known for these amazing accomplishments, Spencer is known in some circles for the mess he made using the signals from this wartime technology. Working in a secret corporate lab one day not long after the end of the war, he and his team were trying to find some way to keep Raytheon rolling in the dough.


Like some '80s evil mastermind, Spencer was working on an elaborate scheme to ensure that his wartime technology did not become obsolete during peacetime. He found it when he walked past a magnetron as it ran in the lab and he became famous - because a candy bar melted in his pocket.

Scientists had noticed this effect even before the war. The radar instruments used were well-known to be able to heat "dielectric materials" for use in the medical industry. Bell Labs, General Electric and RCA all wanted in on the breakthrough that would make this phenomenon useful in the food industry.

In 1933, at the World's Fair in Chicago, Westinghouse cooked steak and potatoes in front of a crowd of onlookers using a shortwave radio transmitter. Somehow, none of them was ever able to go the extra mile - until Spencer.

After melting the chocolate bar, Spencer had an assistant buy other items for experimentation, including popcorn, making Spencer the inventor of not only the microwave, but microwaved popcorn.

The next morning, Spencer modified a tea kettle and put an uncooked egg inside. Upon applying the magnetron, the egg exploded into one of his coworker's faces due to the different rate at which the yolk and the white cooked.

The first true microwave oven was completed when Spencer attached an electromagnetic field generator to an enclosed metal box. By October 1945, Raytheon patented the microwave as the Radarange, and Spencer became famous as the inventor of the first commercial microwave oven instead of his contributions to the allied war victory.

The real bummer here? Spencer only got a $2 gratuity from Raytheon for his invention.


Homemade microwave popcorn in a glass bowl.

Microwaved Popcorn

The first microwave recipe ever - sort of

  • 1 large microwave-safe glass bowl with tight fitting lid
  • 1/3 cup corn kernels

Place the corn kernels in the glass bowl and microwave on high for 6 minutes while listening. When there is 2 seconds between popping sounds, stop the microwave. Enjoy.

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Starting with cold water is the secret to this one minute microwaved poached egg. Travis Grimler / Echo Journal

Microwave Poached Egg

  • 1/2 cup tap water, not warm
  • 1 egg
  • 1 slice toast, buttered
  • Salt and pepper to taste

Place the water into a round bottomed bowl narrow enough that the water still covers the egg when cracked into the water. Be careful to crack the egg into the water and not to slide it down the side of the bowl or it may stick to the bottom.
Microwave the egg for 60-65 seconds. Use a slotted spoon to remove the egg onto your buttered toast. If you like to cut the egg into small pieces to saturate the toast, I recommend seasoning after it has been cut.


Hot, microwaved Spiced Citrus Tea Mix.

Spiced Citrus Tea Mix

From the "Adventures in Microwave Cooking" cookbook by Montgomery Ward

  • 1 cup orange-flavored drink mix
  • 3 ounces sugar-sweetened lemonade mix
  • 1/4 cup instant tea
  • 1/4 teaspoon ground cinnamon
  • 1/4 teaspoon ground cloves
  • Water
  • Cinnamon stick for garnish

Combine all ingredients except the cinnamon stick in a sealable container. Add 1 1/2 teaspoons of the mix or more to taste to a cup and then fill the cup with water and stir. Heat 1 1/2 to 2 minutes on high and serve with a cinnamon stick.
Travis Grimler may be reached at 218-855-5853 or Follow him on Facebook and on Twitter at

Travis Grimler began work at the Echo Journal Jan. 2 of 2013 while the publication was still split in two as the Pine River Journal and Lake Country Echo. He is a full time reporter/photographer/videographer for the paper and operates primarily out of the northern stretch of the coverage area (Hackensack to Jenkins).
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