There are many threads on this forum and the internet in general about "fondant" or bee candy. A good summary recipe is athttp://cheathambees.blogspot.com/2012/01/excellent-fondant-bee-candy-recipe.html
Note the instructions -- add vinegar to invert, don't overheat (use a candy thermometer), and whip vigorously to "whiten" and stiffen.
I agree with Tefer (comment below) that bees reject the fondant in the summer - clean it out of the hive like any intrusion. The crumbles dump through my screen board. Mixing sugar in a mason jar feeder makes a lot more sense. I have top covers cut to fit the lid of a mason jar with a couple of pinholes, put the jar on, and the bees come up through the inner cover to feed. Reduces robbing compared to entrance feeders, and easier to maintain than internal frame feeders, lower volume than dedicated whole super feeders. A homebuilt migratory cover out of used plywood reduces the cost of feeder to the spaghetti sauce you bought to get the mason jar.
That said, let me make some observations about sugars. Artificial nectar copies flower nectar. Flower nectar is primarily a mix of sucrose, fructose and glucose. Sucrose is a "double sugar" -- it is the loosely bonded combination of one fructose and one glucose molecule. Inverting sugar with acid, heat or an enzyme breaks the sucrose into fructose and glucose, yield ing 50% glucose and 50% fructose (or if the process, is as typical, incomplete; some equal amount of F and G with the balance sucrose. Cane sugar is 100% sucrose, but can be decomposed into F and G. Honey is acid, and has been decomposed into (mostly) F and G with about 55% Fructose (due to the native fructose residual presence in raw nectar). High Fructose Corn syrup is 55% Fructose -- it is nearly identical in composition to honey in the major sugars, which is why unscurpulous producers and the Chinese, adulterate honey with HFCS. Honey depending on its source has various other higher sugars, proteins, etc. Notable is Avocado honey (I am locally familiar with this) it has 6% persitol, a higher sugar, and consequently doesn't taste very sweet or very good.
Natural nectars have varying composition, but the nectars that have coevolved to attract European bees tend to have high sucrose content (at 80 to 90% sucrose), and are more concentrated (at 25% sugars) than the nectars for other pollinators (some are low sucrose and tend to be 20-21% sugar (as in hummingbird plants).
So the traditional recipes for feeding and fondant take sucrose and decompose it by inverting to Fructose and Glucose. I have no idea why this is considered better than HFCS -- which is already Fructose and Glucose, save the recipes likely have a residual sucrose component due to incomplete conversion.
There are good lines of research that the many trace components of floral nectar (flavanoids, amino acids, higher sugars) might have important roles. So the sugar syrup (from whatever source) is a junk food that should not be the sole nutrition source.