A desert is a hot and dry place like the Sahara, but add an s and some whipped cream and you have a dessert, a sweet treat to eat. Dessert has two s's because you always want two. (If you prefer two arid ecosystems, that's on you.)
A desert (DEH-zert) is dry, but to desert (deh-ZERT) is to leave someone high and dry. Although desert as a verb is pronounced like dessert, if you desert a friend, you walk away. You don't cover anyone in chocolate.
Here's desert used a noun:
"Even so, the Sonoran desert can feel immense and hostile, with sand and scrub stretching into the horizon." (The Guardian)
And here it is as a verb:
"To befriend them again would be to say, 'It was OK that you deserted us at the lowest point in our lives.'" (Seattle Times)
Informally, a desert can also be a place that's missing something, as in this example:
"The first location was in Watts, long considered a food desert, or an urban area lacking convenient and quality food and dining options at reasonable prices." (Los Angeles Times)
Dessert, on the other hand, has an extra s for the strawberry shortcake at the end of a meal. Some people might have cheese after dinner, but a dessert is usually sweet, like oatmeal cookies or apple pie. Here are a couple of delicious examples:
"The key lime pie, topped with extra-thick whipped cream, is the best-selling dessert." (Washington Post)"True to its classic form, the dessert consisted of two layers of sponge cake, a thick center of yellow cream and a chocolate-frosted top." (Wall Street Journal)
So remember, don't get a desert mixed up with your dessert or else you'll wind up with sand in your strawberry shortcake. See what we did there?