Preheat your oven to 350°F / 175°C and line a large baking sheet with parchment paper.
In a medium bowl, combine the pecan halves, brown sugar substitute, heavy whipping cream, and vanilla extract.
Stir until the pecans are fully and evenly coated.
Spread the coated pecans in a single, even layer on the prepared baking sheet.
Bake for 10 minutes, then remove the pan from the oven and stir the pecans.
Spread them back into an even layer.
Return the pan to the oven and bake for another 8-10 minutes, or until the coating is bubbly and the pecans are a deep golden brown.
Remove from the oven and immediately sprinkle with sea salt, if using.
Let the pecans cool completely on the pan before breaking them apart. Store in an airtight container at room temperature for up to 2 weeks.
Keep a close eye on the pecans during the last few minutes of baking. The sweetener can go from perfectly caramelized to burnt very quickly.