01 - Strain fresh watermelon juice through a fine mesh sieve, ensuring all pulp and seeds are completely removed for a smooth texture.
02 - In a medium saucepan, whisk together granulated sugar and cornstarch until thoroughly blended and no lumps remain.
03 - Gradually pour the strained watermelon juice into the dry mixture while whisking continuously to prevent clumping and achieve a smooth consistency.
04 - Stir in lemon zest and vanilla extract, distributing evenly throughout the mixture.
05 - Place saucepan over medium heat, stirring constantly to prevent scorching. Continue cooking for 8-10 minutes until the mixture reaches a soft pudding consistency and coats the back of a spoon.
06 - Remove from heat source. If using dark chocolate chips for traditional appearance, gently fold them into the warm pudding.
07 - Pour the pudding into individual serving glasses or molds. Allow to cool completely at room temperature, then refrigerate for minimum 3 hours until fully set.
08 - Just before serving, sprinkle generously with chopped pistachios. Optionally add dried rose petals and extra chocolate chips for visual appeal.