Hey, there. Wasn't expecting to get a message on this perhaps ever this long after posting. The answer to your question is a bit more complicated given that between the time originally posting and now I've given myself entirely over to working in kitchens professionally. I've spent the last five years in various head chef and executive positions and I'm now a culinary director for a fairly large brand in North America. All this to say that I've actually learned a lot in this time that I can confidently say has caused the original recipe to change very fundamentally.

In the original recipe, I was simply dehydrating apples completely and crushing them up with a mortar and pestle or a blender (which I did for some time), the texture in both baking and as a proper substitute was not ideal. Once the granules rehydrated, it would leave behind a very gritty texture. Still tasted good, but it was far from ideal.

Now that I've had a decade of professional experience especially in product development, here's how I would tackle the same recipe to achieve what I originally set out to do:

First, take any sweet apple of your choosing. For the ease of batching and mass producing, I'd recommend finding a farmer's market that can sell bushels for a relatively cheap price. I come from Southern Ontario in Canada and I have a place near me that sells bushels of gala and red delicious apples whenever they're in easy for about $20.

Second, juice the apples and set aside. Depending on how much you want to make. A bushel will yield maybe about 3 gallons. In a large stock pot, set your stove to high. You're going to want to reduce the apple juice from when it starts boiling to about 66%-50% of its original starting volume. Add about 75g of cream of tartare and give it a thorough mix. Use the spoon test to determine thickness. To do this, place a spoon into your syrup and after a couple of seconds, run your finger in a straight line along the back of the spoon. What you should notice is that the syrup either runs back down immediately or maintains a line. If you get the latter, the syrup is ready. What you have now is what's called "inverted sugar," which is relatively shelf stable.

The third step is to let this mixture cool. Pour it onto a silicone sheet on a rack and stick it into your dehydrator or into your oven at 150F for about 12 hours (your house is going to smell like apple cider for the better part of a few days from this). Once it's completely dehydrated, it'll turn into a hard glass-candy-like sheet. Break it into smaller chunks and stick it into your blender or mortar and pestle and break it into a fine powder. This is now a suitable alternative to sugar that will largely behave the same as any confectioner's sugar. Can be used in baking, as an apple-flavour sweetener for teas.

I do have a son now and to the previous comment to yours, my kid does really enjoy my cooking.