Cilantro Roast Cod and Cabbage With Herb Salad

Name: Cilantro Roast Cod and Cabbage With Herb Salad
Ingredients: 3 garlic cloves; 1 5 piece ginger, peeled, coarsely chopped; ½ serrano chile, stem removed; 3 Tbsp. fish sauce; 2 Tbsp. honey; 2 Tbsp. black peppercorns; ½ bunch cilantro, plus ⅓ cup cilantro leaves with tender stems; 2 small shallots, thinly sliced, divided; ½ cup avocado oil or vegetable oil, divided; 1 Tbsp. plus ½ tsp. Diamond Crystal or 2 tsp. Morton kosher salt, plus more; 1 2-lb. cod fillet, cut into 6–8 pieces; 1 small head of green cabbage (about 2 lb.), cut into 8 1½-thick wedges; ⅓ cup mint leaves; 1 Tbsp. extra-virgin olive oil; Lime wedges (for serving)