Add add water and heat to dissolve - check gravity. Adjust to proper gravity, bingo, it's syrup.
Or (for home use) strain out the sugar, use the syrup, use the sugar. That's assuming it's liquid with crystals, as for slight over-heat.
or dump it in a pan, boil it more, and make sugar seriously (unless it's already there, in which case, use it.)
Two turkey pans on cinderblocks in the 1970's
4x5 no-baffle stainless pan, built sugarhouse ~1980 - buckets and snowshoes. 17 gallons in best year. Went off to college, nothing for 25+ years.
Thinking about getting going again in new location, in a small way. •• Cats, Coffee, Chocolate...Vices to Live By.