Years ago I was really missing it and my wife found a Josta taste a like recipe. It was Bawls, Sobe Dragonfruit, and Pepsi.

Here is a recipe for Josta

Making Josta Reborn

Required items
20oz Pepsi
20oz SoBe Dragon
10oz Bawls
16oz or bigger measuring cup
1oz measuring cup
drinking cup or spare bottle
Optional Printed Josta Reborn label

Process
Carefully and slowly open the Pepsi being as careful as possible not to cause more bubbles than necessary.
Bring bottle to the edge of the larger measuring cup and rest it on the edge, tipping it slowly and empty out 7.7 Ounces of the Pepsi. gently set the Pepsi bottle down when done.
Empty the 7.7 ounces of pepsi in to the drinking cup or spare bottle. You may consume this now so you dont waste good cola.
Open the SoBe Dragon and pour 6.7 ounces in to the large measuring cup.
Open the bawls and measure out 1 ounce in to the small measuring cup and then add it to the 6.7 ounces of SoBe Dragon. Gently pick up the partial Pepsi Bottle and tip it at a 45 degree angle. In the other hand, pick up the measuring cup with the Sobe and Bawls mixand rest it on the Pepsi Bottles opening.
SLOWLY pour the Sobe and Bawls mix in to the Pepsi Bottle allowing it to trickle down the inside surface of the bottle. If you do it right it should take you about 10 to 15 seconds to finish, and there should be NO bubbles being provoked form the Pepsi from the very slow speed at which the liquids meet.
Put down the now empty measuring cup and gently place and tighten the cap back to the Pepsi Bottle.
Carefully, slowly, and gently tip the closed bottle back and forth to ensure and even mixture.
Optionally apply label if youd like.
For best results, put it in the fridge for a few hours. this will allow the beverage to chill and build up a little carbonation. a bottle that remains in the fridge over night will have nearly the same pressure feeling when squeezing it as an unopened bottle of soda.

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