Toast the fennel seeds in a small skillet over medium heat just until they start to change color.

NPR: Recipe: 'Good Day for a Picnic'

Mr. Mattos calls for tossing the chicken pieces with pungent garlic, hot chili flakes and sweet fennel seeds.

WSJ: Ignacio Mattos's Fennel, Chili and Yogurt Roast Chicken with Parsley Salad | Slow Food Fast