Add blackberry concentrate/puree and1/2 cup of water to small pot on high heat, add sliced jalapeno and bring to a boil. Lower heat and simmer for 5 minutes. Let cool.
In a separate heavy bottom or copper pot, add sugar, blackberry mixture (strain the jalapenos) and cream of tartar. Stir until sugar dissolves and mixture starts to boil. At this point do not stir any further. Wash down the inside of the pot with a wet brush to dissolve any sugar crystals formed on the sides of pot.
While sugar is cooking. Line a baking sheet with parchment paper, sprinkle the tajin on the sheet and spread out evenly. Use more if you need more coverage. This will be where you rest the apples and will prevent the apples from sticking to parchment paper. Insert sticks into apples.
Cook sugar to 300 degrees and immediately remove from heat. Let cool for a couple of minutes.
Dip apples one at a time into the candy mixture and place it on the tajin. You can also try spooning candy over apples. If candy starts to thicken, heat it up again so its easier to cover the apples. Be very careful, candy is super hot.
Let candy cool for about 10 minutes and enjoy.