Combine the Watermelon Sour Punch Straws and a splash of water in a saucepan and bring to a simmer over low heat.

Stir continuously to prevent the candy from sticking to the pan, adding more water, up to ½ cup, as necessary until melted.

Turn off the heat and scoop the melted Sour Punch into a bowl.

Combine the sugar and the remaining ½ cup of water in a saucepan and simmer over low heat until dissolved, about a minute. Set aside.

Add the sugar water, lemon juice, and melted Watermelon Sour Punch Straws to a blender and blend until completely smooth.

Place a fine mesh strainer over a bowl and pour the mixture through to catch any little chunks.

Add the mint leaves to a pitcher followed by the lemon slices (reserve a few slices for garnishing the glasses).

Pour the blended Sour Punch mixture into the pitcher followed by the sparkling water and stir to combine.

Fill four glasses with ice.

Pour the sparkling watermelon mint lemonade into each glass and garnish with lemon slices and fresh mint.