Sprinkle the spice blend all over the chicken breasts, drizzle with 1 tablespoon olive oil, and use your hands to rub into the chicken. Place the chicken on 1 large baking sheet (or 2 standard sized baking sheets).
Toss the potatoes and broccoli with 2 tablespoons olive oil and 1 teaspoon salt and add them to the baking sheet as well as the lemon wedges around the chicken breasts.
Roast until the chicken is cooked through and the veggies are tender, about 40-45 minutes.
Serve each plate with a wedge of lemon for drizzling.
Notes
Use your favorite spice blend such as Herbs de Provence, Moroccan Italian Herbs, Cajon Seasonings, etc in place of the Harissa Spice Blend.