A Gastrique Primer, or How to Improve Your Next Tomato Sauce

Vinegar and sugar can spruce up any sauce.

Once we had blanched and peeled the tomatoes we chopped them, strained the seeds, and simmered it for twenty minutes into a simple sauce. Then I made my gastrique , which involved no measuring -- maybe 1/4 cup of vinegar and 3 tablespoons of sugar -- and a quick boil into something thick and syrupy.

I tasted the sauce before adding it, which was fine, clean and simple.  And then I tast...