Spicy Grilled Butterflied Chicken with Crispy Bread

Name: Spicy Grilled Butterflied Chicken with Crispy Bread
Ingredients: One 4-pound chicken; Grapeseed oil, for drizzling; 2 large lemons, zested and halved; 2 tablespoons chili powder; 2 teaspoons sweet smoked paprika; 2 teaspoons cayenne pepper; 1 teaspoon ground cumin; 1/2 teaspoon garlic powder; Kosher salt and freshly ground black pepper; 1 loaf rustic bread, such as ciabatta or pain rustique, halved lengthwise; Extra-virgin olive oil, for drizzling; 3 scallions, thinly sliced; 1/4 cup flat-leaf parsley leaves, roughly chopped