Is the caramel recipe wrong, or is it my technique? Twice now, I've made the "Ultimate Tarte Tatin" recipe from the Food Network site. In both cases, the crust and apples worked out perfectly.

And in both cases, the caramel seemed to come together before adding the apples, but never really firmed up and remained a thin liquid throughout the cooking process and afterwards.  Tasty, but not really caramel at all, and not a successful pie.

The caramel is 3/4 cup sugar + 2 tbsp water, and 1/2 stick butter.  The instructions are brief, probably fine if you know what you're doing. I'm a caramel novice.  

Any suggestions on better or more specific ratios, or more-foolproof techniques, would be appreciated.
I like the recipe from Gourmet magazine because I don't have to try to stand apples up in hot caramel. It uses the same amount of butter, less sugar, and no water. Works for me every time.