Just pop the sugar in a pan, cook until melted, then turn caramel
This is what I do when I make flan. I use a small enameled or stainless steel frying pan and heat up the sugar stirring pretty much constantly. At first it clumps together kind of like rock candy and then it gradually melts and turns brown. QUICKLY pour into baking dish because it hardens fast. It never really covers the whole bottom, but as the flan cooks it spreads out and always turns out just fine.