Line a 9x13 baking sheet with parchment. Your pan needs to have sides, so the candy does not spread over the edge when poured.
Place your candy thermometer on the side of a medium saucepan, making sure the tip of the thermometer does not touch the bottom of the pan.
Measure out all of your ingredients before you begin as the addition of ingredients in step two happens fast.
Add the 1 cup corn syrup, 1 cup sugar and 1 Tablespoon vinegar to the pot and bring to a boil on medium heat, stirring frequently.
When your liquid mixture reaches 285 degrees, move the pan to a cold burner and immediately stir in your remaining ingredients (vanilla and baking soda) until JUST incorporated. It is very important that you do not overmix.
Your mixture will bubble up quickly when the baking soda and vinegar meet. Do not keep mixing as you will knock out the air bubbles.
Quickly pour your bubbling mixture onto your parchment lines pan and let sit for about 30 minutes.
After 30 minutes, lift your parchment paper to free the candy and break into chunks. Dropping the candy can help. Also hitting with a rolling pin.