I regularly making Panforte which involves heating an equal parts mix of honey and sugar to 115c. Due to the quantity of sugar a jam thermometer doesn't normally reach the mix in the bottom of the pan to work effectively. My technique at the moment is to stir it and every now and again tilt the pan to pool the honey and then use a normal but cheap probe thermometer. However, sometimes the mix visually looks much hotter (small bubbles, more 'activity') but still reads lower than my desired temperature.
In the finished bake I am getting very inconsistent results in terms of consistently; sometimes they are very soft and other times very hard and brittle. Given the baking times are the same I can only assume the inconsistency is due to the inaccuracy of measuring the temp of the sugar/honey mix.
So my question is is there anything wrong with the technique described above? Why might it be inconsistent? Or is there a better way to accurately take the temperature of the sugar honey mix? Would an IR thermometer be more useful than a probe?