01 - Line an 8x8 inch baking pan with parchment paper and lightly grease the surface to prevent sticking.
02 - In a small saucepan, mix watermelon puree, corn syrup, and lemon juice. Stir thoroughly to combine all ingredients.
03 - Sprinkle gelatin powder evenly over the fruit mixture. Let stand for 5 minutes to allow the gelatin to hydrate and bloom.
04 - Add granulated sugar to the saucepan. Warm over medium-low heat, stirring constantly, until gelatin and sugar completely dissolve. Do not allow the mixture to boil.
05 - Pour the hot mixture into the prepared baking pan. Smooth the surface with an offset spatula. Let cool at room temperature for 30 minutes.
06 - Refrigerate the pan uncovered for 2 hours or until the candy is completely set and firm to the touch.
07 - In a small bowl, combine 1/3 cup granulated sugar and citric acid powder. Mix well to distribute evenly.
08 - Cut the set candy into small squares using a sharp knife. Roll each piece in the sour sugar mixture, ensuring all sides are evenly coated.
09 - Store finished chews in an airtight container, separating layers with wax paper to prevent sticking. Best consumed within one week for optimal texture.