Spray slow cooker with cooking spray. Make a layer of half the potatoes. Sprinkle with half the white parts of the green onions, half the garlic, 1/2 teaspoon oregano, half the salt, and half the pepper. Top with half the lemon peel strips and 2 lemon slices. Repeat with another layer; do not stir.
Place chicken on vegetables. Sprinkle with the final 1/2 teaspoon oregano. Top each piece of chicken with 1 slice of lemon. Pour lemon juice around, not over, the chicken. Cook, covered, on low for 4 to 6 hours, or until chicken is no longer pink in the center. Serve chicken with potato mixture and cooking liquid. Garnish with tomatoes, feta and green parts of the green onions. Makes 4 servings.
Approximate Nutrient Analysis per serving:
300 calories, 5 g fat, 1.5 g saturated fat, 75 mg cholesterol, 400 mg sodium, 36 g carbohydrate, 5 g fiber, 4 g sugar, 30 g protein