Feta Brined Roast Chicken

Name: Feta-Brined Roast Chicken
Ingredients: One 3½-lb. whole chicken; 2 oz. feta cheese (about ⅓ cup); 1 Tbsp. black peppercorns; 5 oregano sprigs; 2 garlic cloves, smashed and peeled; 1 dried bay leaf; 1 medium lemon, thinly sliced; 1 Tbsp. vegetable oil; ¼ cup extra-virgin olive oil; 1 Fresno chile or red jalapeño, thinly sliced crosswise (seeded if desired); 2 Tbsp. chopped mint, plus more for garnish; 2 Tbsp. chopped parsley; 2 Tbsp. thinly sliced scallions; 1 tsp. paprika; ¼ tsp. dried oregano; 1 medium lemon; ¼ cup crumbled feta cheese