Copycat Garrett's Popcorn - Caramel Popcorn Recipe For the Caramel Popcorn: Place the brown sugar, butter, corn syrup, salt and vanilla in a large microwave safe bowl. Microwave on high for 2 minutes. Stir, then microwave another 2 minutes, until boiling. Immediately stir in the baking soda and pour over the popcorn in one bag.