This is a clear, syrupy caramel sauce which goes well on ice cream, cheesecake, plain cake, filled dessert crepes - almost anything you'd want caramel sauce on, although intensely chocolate things tend to overwhelm it. I call it "double serendipity" because of two "mistakes" I made that turned it from a fairly basic caramel syrup into something with a deep, intriguing flavor.
The first mistake was that I put a dollop of Lyle's Golden Syrup(*) in at the beginning. The cookbook I was looking at had two recipes for caramel sauce, a clear one and one made with cream, and they were on facing pages. The recipes started out the same, but the cream sauce called for golden syrup. When I realized my mistake, I figured it wouldn't make any difference in the end, and it would give it more flavor.
The second mistake I made was to cook the first batch too long; when it cooled, it wasn't spoonable. I had to add more water and boil it some more to get the proper consistency. I had added the flavorings at the end of the first cooking process, which is normal, but they got thoroughly boiled when I re-cooked the mixture. The taste was ambrosial! The second time I made it, I cooked it the right amount of time, and added the liquor and vanilla at the end again... and it was just rum-flavored caramel sauce, tasty enough, but nothing special. Somehow adding the flavorings before
the final boiling cooks off the raw alcohol taste and makes everything meld together into a uniquely delicious flavor. (And one of these days I'm going to try adding a bit of sea salt.)
DOUBLE SERENDIPITY CARAMEL SAUCE
1 cup granulated sugar [200 g caster sugar]
1/4 cup [60 ml] water
1 very heaping tablespoonful of Lyle's Golden Syrup(*)
Have ready by the stove:
1 cup [240 ml] very hot water
3 tablespoons [45 ml] dark rum (I use Appleton's Jamaica Rum, which is very flavorful)
1 tablespoon [15 ml] pure vanilla extract
Place the sugar, the smaller amount of water, and the syrup in a heavy saucepan with a capacity of at least 1 quart [1 liter]. Cook and stir over moderately high heat until everything is thoroughly dissolved, then stop stirring and watch it until it turns a deep golden color, but don't let it get too dark or it will start to taste bitter. Remove the pan from the head and slowly and carefully add the larger amonut of water - it will boil up in a great hissing, bubbling fuss. Stir a bit, then add the rum and vanilla, which will probably bubble up a little more. Return the pot to the stove, reduce the heat a little, and stir until everything is dissolved again. Bring it back to the boil and stop stirring. Boil it until it has reduced to 1 cup [240 ml] in volume; I periodically pour it into the heatproof cup I measured the water in, and then pour it back into the pan if it needs to cook more. When it's done, let it cool in the heatproof cup until it's just warm, then pour it into a jar with a lid. Store, covered, at room temperature. (If your room is chilly, after a couple of days the syrup may start to form crystals around the edges; if they bother you, reheat it gently while stirring.)
(*) Lyle's Golden Syrup is a British product that is now found in many US supermarkets. It's "refiner's syrup", the thick, golden, slightly brown-sugar flavored syrup that's left at the end of the sugar-refining process. It not only adds color and flavor, it helps prevent candies and sauces from crystallizing.