Seafoam Candy

Ever since I was little I lived for getting a piece of milk chocolate seafoam from Rocky Mountain Chocolate Factory. I haven't dabbled much in candy making but decided to try and recreate seafoam using Joy the Baker's recipe. It was kind-of intimidating because it involves heating a bubbling mass of sugar, vinegar, and corn syrup until it's 300-degrees, then immersing it in cold water, whisking in baking powder, and then quickly spreading it out onto a pan. 

After letting it harden for 20 minutes I cracked it using a metal ladle and drizzled semi-sweet chocolate and sea salt over the pieces. 

Overall I was disappointed in the lack of "foaminess" of the candy. It came out more as hard candy and there weren't very many bubbles like there are in a Violet Crumble bar. A couple things could have been at play--perhaps my thermometer wasn't calibrated or the high altitude of my home made something not quite work right. Also it looks like there is some disagreement in the DIY seafoam world about if you need to use vinegar or not to achieve the reaction with the baking soda to make it bubbly. I think if I try it again I'll use a different recipe without vinegar and invest in a new candy thermometer. Overall the shards of candy were tasty, especially when covered with chocolate and salt, but they are definitely more on the hard candy side and you have to be careful not to pull out any dental work! Does anyone have a seafoam recipe they've had good success with? Let me know if you do!