This mustard sauce, ham’s best friend, hails from my mother-in-law’s family and is as essential to my wife’s family’s Christmas spread as matzo balls are to my family’s Passover Seder. The sauce is a small victory not only for its familial significance but also because it demonstrates how to perfectly balance sweet with sour—the key to so many successful things in the kitchen (think great salad dressing or cocktails). I was introduced to the sauce alongside a pile of thinly sliced country ham and plenty of warm biscuits (store-bought are fine), which I love, but it also makes for a great glaze for grilled pork chops or chicken (check out the Spin-Offs for even more ideas). Store any leftover sauce (unlikely) in an airtight container in the refrigerator for up to a week (warm over low heat before serving).



SERVES 6 TO 8; MAKES 1 1 /2 CUPS [360 ML] SAUCE
 1 cup [200 g] sugar
1 egg
 1 Tbsp yellow mustard powder
 1 /4 cup [60 ml] white wine vinegar
8 oz [230 g] country ham, thinly sliced
12 warm Everything Biscuits , made without the seeds

In a small saucepan over medium heat, combine the sugar, egg, mustard powder, and vinegar and whisk together. Bring to a boil, whisking constantly, and boil until thick and glossy, about 3 minutes. Transfer the sauce to a serving bowl and serve warm alongside the ham and biscuits.

NOTE: If you find yourself with a not-totally-smooth sauce (i.e., with bits of cooked egg), simply strain it through a fine-mesh sieve before serving.

SPIN-OFFS

SUBSTITUTE ENGLISH MUSTARD POWDER to make the
sauce even sharper. Or add hot sauce and/or cayenne pepper to
make it extra spicy.

DRIZZLE THE SAUCE ON BACON toward the very end of
frying to glaze it. Alternatively, place strips of bacon on a rack set
over a baking sheet, brush with the sauce, and bake at 400°F
[200°C] until crisp.

TO TURN THE SAUCE INTO MUSTARD BBQ SAUCE (à la
South Carolina), substitute light brown sugar for the regular sugar
and add 1 Tbsp Worcestershire sauce to the mixture. Serve with
pulled pork, on grilled pork tenderloin, or even on broiled salmon.

Oh, and ribs! Put it on ribs!