It might sound like a lot of trouble to rearrange the atoms of your household sugar to create moister, more velvety treats, control sugar crystallization, retard spoilage and intensify delicious aromas. Surprisingly, it's not an arduous process at all: three ingredients and a few minutes are all it takes to "invert" household sucrose, using heat and a catalyst to change the configuration of the sugar's molecules in a way that magically makes your baking sing. Here's a significant bonus for health-minded bakers: Inverting household sugar also increases the sugar's sweetness. Invert syrup is 30 percent sweeter than table sugar. Therefore, carb-counting cooks may cut down on the total sugar in a recipe when substituting its inverted counterpart.
Pour equal parts extra-fine, granulated white sugar, filtered water and a small spoonful of lemon juice or cream of tartar into the saucepan. Leave plenty of room in the pan to accommodate a rolling boil. Stir well to combine.
Insert the food thermometer into the mixture.
Set the stovetop to medium heat and bring to a rolling boil.
Dip the pastry brush in water and gently brush away any crystallized sugar from the sides of the pan. Keep dipping the pastry brush in water as you do this to prevent crystallization on the brush. Don't worry about introducing extra water into the mix, as it won't have any effect on the final product.
Without further stirring, heat the mixture until it reaches 236 degrees Fahrenheit.
Remove the pan from the heat to the trivet, and place the tight-fitting lid on the pan.
Let cool at room temperature. Do not cool in the refrigerator.
When cool, decant into the glass storage container. A mason jar works well for this purpose, as the wide mouth makes it easy to access the slow-flowing syrup with a measuring spoon or cup.