01 - Line a baking sheet with parchment paper and set aside for later use.
02 - In a large, heavy-bottomed saucepan, combine the granulated sugar, brown sugar, and heavy cream. Stir thoroughly to blend all ingredients.
03 - Place the pan over medium heat and stir constantly until the sugars completely dissolve and the mixture begins to bubble.
04 - Add the butter to the hot sugar mixture and stir continuously until fully melted and incorporated.
05 - Attach a candy thermometer to the pan. Continue cooking, stirring frequently, until the mixture reaches 238°F (soft-ball stage), approximately 10-15 minutes.
06 - Remove from heat. Immediately add the vanilla extract, salt, and pecan halves. Stir vigorously for 2-3 minutes until the mixture thickens and becomes creamy while remaining pourable.
07 - Working quickly, drop spoonfuls of the mixture onto the prepared baking sheet, spacing each praline approximately 2 inches apart.
08 - Allow the pralines to cool completely at room temperature until fully set, about 20-30 minutes.