I've been making small batches of hard candy using my own flavor extracts. My problem is that after several highly successful batches I've started having trouble with the candy being tacky and a bit soft. Based on many recipes I've seen online I've been using 1/3 cup light corn syrup for every cup of sugar, mixed with enough water to keep the sugar from burning before it comes to a boil. The batch I made yesterday was 2 cups sugar, 2/3 cup light corn syrup, mixed with about 3/4 cup water. I bring the mix to a boil over med-high heat. Once the foam has subsided, I cover for five minutes. When the cover is removed I attach a good quality digital thermometer (which is within 1 degree on the boiling water test), ensuring it's submerged but not touching the bottom of the pan. When the temperature hits 280F I reduce the heat to med-low and add the food coloring. (I've been using a couple drops of a gel coloring.) When the temp consistently stays above 305F, I turn off the flame and begin to gently move a silicone spoon around the pot just to keep a bit of motion. (When I just let it sit undisturbed I found the bottom and sides stayed very hot and liquid while the center top got quite solid. I started gently stirring on the next batch.) When the bubbling stops, usually around 290F, I gently stir in the extract. The extracts all have 80 proof vodka as the solvent. The amount of extract varies depending on the batch. This last batch of cinnamon was a bit weak so I used 2 Tblsp plus 1/4 tsp vanilla. When the candy has stopped bubbling from the extract, I pour into silicone molds. My very first batch of candy crystallized, but I've had no issues with that at all since that first time. I had one batch that was a bit tacky after cooling. That's when I started turning down the flame at 280F to be sure I was getting the whole mix up to temp and not having pockets that were much hotter. I had very good results for several batches after that. My problem is that my recent batches have been tacky and slightly soft. It's basically hard, but you can form it to the roof of your mouth by pushing with your tongue and it has a tendency to stick to the teeth. The batches I considered complete successes were rock hard all the way until they fully dissolved. I'm pretty careful about getting the temp very close to 310F before taking it off heat so I don't think the issue is too much water left in the mix. I must admit I've been a bit cavalier about measuring the corn syrup, generally using the same one cup measure I use for the sugar and just eyeballing the portion. This makes me wonder if I'm using too much corn syrup. The other thing that struck me is that I had been using Karo but fairly recent bought a large bottle of house brand light corn syrup. I had figured corn syrup was corn syrup, but now I'm wondering if that may be the root of the problem. I've also read that some people insist on using cane sugar, not beet sugar. The sugar I've been using is refined from beets, but I've been using the same brand of sugar all along so I don't think that's the problem. Sorry for the book but I wanted to be sure I fully explained the situation and included enough detail to get good advice. Any ideas on what's going wrong? Too much corn syrup? Bad brand of corn syrup? Do I really need more than a few tablespoons of corn syrup?