Season chicken with salt and pepper. Heat oil in a medium nonstick skillet over medium heat. Add shallots; cook 2 to 3 minutes or until translucent. Add garlic; cook until fragrant. Stir in chicken and cook about 5 minutes, until browned on all sides; remove chicken from skillet. Add wine and juice to skillet and simmer for 2 to 3 minutes until about 3 tablespoons of sauce remains. Stir in butter. Return chicken to skillet.

Meanwhile, in a separate wide, nonstick skillet over medium-high heat, heat oil and garlic and cook until garlic turns light gold. Add spinach; toss and cook 1 to 2 minutes or until it becomes limp and bright green in color. Season with salt and pepper. Remove spinach from skillet and place in a thin layer on a serving platter. Spoon chicken and sauce over spinach.