Crisp Winter Lettuces with Warm Sweet-and-Sharp Dressing

Tear greens into large pieces and put in a large salad bowl with arugula, scallions, and chives.

Cook bacon in a 12-inch nonreactive skillet over medium heat until crisp. Transfer bacon to paper towels to drain, then stir vinegar, sugars, salt, and 1/2 teaspoon pepper into fat in skillet. Boil, stirring occasionally, until reduced to about 3/4 cup, 10 to 12 minutes. (Dressing should be syrupy and bubbling.)

Crumble bacon over salad, then toss with enough warm dressing to lightly coat. Season with salt and pepper.