In a small saucepan, add the butter, sweetener and salt. Stir together and bring to a boil over medium heat.
Once boiling reduce heat to low and stir constantly. The color will change to a dark brown, continue to stir until it reaches 300 degrees using a thermometer.
Turn heat off, add vanilla extract, caramel extract and vanilla stevia and stir together. Add baking soda, stir together then add nuts.
Pour the mixture on the baking sheet pan and spread the nuts in an even layer.
Allow to set on counter for 30 minutes then you should be able to break it into pieces. You can also refrigerate to set.