Preheat oven to 400°.
Line a baking sheet with foil, and coat the foil with cooking spray.
Combine turkey and next 7 ingredients in a large bowl. Shape into 36 (1-inch) meatballs, and place on a baking sheet. Bake at 400° for 15 to 17 minutes or until centers are no longer pink. Set aside, and keep warm.
Combine 1/2 cup chicken broth and 3 tablespoons flour; stir with a whisk until smooth.
Pour remaining broth into a large saucepan; bring to a boil. Slowly add flour mixture to broth, stirring constantly. Cook over medium heat until mixture thickens and returns to a boil, stirring constantly. Add lemon juice and next 3 ingredients, stirring well.
Remove from heat, and stir in sour cream. Add meatballs, and stir gently. Cook over low heat until thoroughly heated.