Grilled Cabbage With Preserved Lemon Mostarda

Name: Grilled Cabbage With Preserved Lemon Mostarda
Ingredients: For the grilled greens:; 1 head green cabbage, cored and halved, then cut into thirds lengthwise; 4 to 5 scallions, ends trimmed; 2 tablespoons extra-virgin olive oil; 2 teaspoons kosher salt; For the mostarda:; 3 tablespoons extra-virgin olive oil; 1 preserved lemon peel, finely chopped; 1 tablespoon Dijon mustard; 1/8 teaspoon granulated sugar; Kosher salt, to taste; Freshly cracked black pepper, to taste; 2 tablespoons capers, drained and roughly chopped