Line a large baking sheet with parchment paper and coat with non stick cooking spray.
In a large saucepan over medium heat, combine sugar, corn syrup, butter and bring to a boil and cook or until a candy thermometer registers 275 degrees F, about 17 minutes.
Stir the peanuts into the syrup mixture and continue to boil, stirring constantly, until a candy thermometer registers 295 degrees F, about 3 minutes.
Remove hot syrup from the heat and carefully stir in baking soda and chipotle chile powder. Quickly pour mixture onto prepared baking sheet and cover with another sheet of parchment paper.
Using a rolling pin, quickly roll mixture to an even thickness.
Discard top parchment sheet and allow peanut brittle to cool completely.
Break peanut brittle into smaller pieces and store in airtight container up to 2 months.
Notes
You will get about 1¾ pounds of peanut brittle with 1 ounce of brittle being 1 serving.