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