Sprinkle chicken thighs evenly with salt and 1/2 teaspoon pepper.
Heat 1 tablespoon oil in a large skillet over medium heat; add half of chicken. Cook about 3 minutes per side, or until browned. Remove from skillet and place on a plate. Add remaining 1 tablespoon olive oil to skillet, and repeat browning procedure with remaining chicken.
Spray bottom and sides of slow cooker with nonstick spray. Place potatoes on bottom of cooker. Place chicken on top of potatoes.
In a mixing bowl, whisk together broth, juice, flour, and garlic, stirring with a whisk. Pour broth mixture over chicken. Top with remaining 1/2 teaspoon pepper. Cover and cook on low heat for 6 hours or on high heat for 4 hours.