1Heat oven to 425°F.
2Cut potatoes into halves, or into quarters if larger; place cut side down in 10-inch cast iron skillet. Sprinkle potatoes with dash salt. Layer about 5 lemon slices over top.
3Pat chicken dry with paper towels; remove any giblets. Stuff cavity of chicken with any remaining lemon slices. In small bowl, stir together sage, garlic, 1 teaspoon salt, the pepper and olive oil. Rub sage-garlic mixture beneath breast skin of chicken and all over outside of chicken skin. Place chicken on bed of potatoes and lemon.
4Roast about 1 hour 30 minutes or until instant-read thermometer inserted into thickest part of thigh reads 165°F. Let chicken rest about 15 minutes before carving.