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This Watermelon Smoothie is the most refreshing summer beverage you will ever try. And, yes, it really is low carb and keto!

I spent many years working at Friendly’s as a waitress. From when I was 17 off and on until I got married at 21. By the time I quit right before my wedding and college graduation, I knew what my menu favorites were. My favorite beverage was the Frozen Watermelon Slammer. It is made with watermelon sherbet and sprite. I’ve been craving one the past few years and I’m thrilled to now have a low carb and sugar-free watermelon smoothie alternative.

My mom hates anything watermelon flavored (she does love real watermelon) but I love it. I also love anything cotton candy flavored and my favorite Italian Ice as a kid was banana. I remember getting it from the Italian Ice truck during summer camp. It was bright yellow and tasted like the bananas in Runts candy. I might be the only one in the world with that as their favorite. What is your favorite Italian ice or popsicle flavor? Tell me in the comments, I’d love to hear!

When I found out that Lorann flavoring oils came in watermelon it made my day. (They do also come in cotton candy, banana, and a hundred other flavors). I can buy these at a local candy making store but they are also sold on Amazon. There are a few sellers that let you pick 12 different flavors for $15. I use the cinnamon oil in my Red Hot Gummies and the orange oil in my Creamsicle Gummies.

Ingredients in the Watermelon Smoothie: sweetener, half and half or heavy cream, lemon-lime seltzer, watermelon flavoring oil, lemon extract, vanilla extract, ice cubes, xantham gum (optional, keeps the drink from separating)

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Originally Published on May 21, 2016. Revised and Republished on May 15, 2018.