Receipe is a bit strong but this is what I do:
Clean killer style jar, prep carrots using a mandolin, currently in the round, don't think batons will be as versatile, might do strips like peeling, (no doubt others will advise correct terminologies) pack carrots in jar about half way add a quarter of a supermarket dill packet , repeat until about 3-5 mm from top of jar. In suitable pan "eyeball" 50/50 ish mix of white vinegar & apple cider vinegar to fill the void, pinch of salt, about 100-150gms of sugar, splash of water, heat gently until sugar dissolved, taste test, adjust as you per your taste, pour into jar till carrots covered & just below full, allow to cool, seal put in the fridge, can be tried after an hour or two. @ADAMG let me know what you think