Spread the pecans out on a microwave safe plate, microwave the nuts for 1 minute to toast. Rotate the nuts and do 1 more minute if you like them extra toasty, but be careful not to burn. Some microwaves are very strong.
In a large saucepan combine sugars, buttermilk, baking soda, butter and vanilla extract
Stir the ingredients together with a wooden spoon over medium low heat until everything is melted together
Add a candy thermometer to the pan and stir periodically until the mixture reaches 235 degrees
As soon as it reaches 235 degrees, remove the pan from the heat. Add the toasted pecans and stir with a wooden spoon.
Stir the mixture for 1-2 minutes until is starts to slightly thicken. You can tell it is thickening because the mixture will look a little more cloudy.
Be careful to not over mix or the candy can seize. Don't mix longer than 2 minutes.
Spoon the candy into little circle shapes on a parchment paper and let them set for 10 minutes or so. You should have about 16 circles of candy.