Coat chicken with yogurt, cover, and refrigerate at least 2 hours, preferably overnight.
Rinse chicken, and pat dry with paper towels.
In a bowl, stir together flour, paprika, salt, and pepper.
Heat oil, margarine, and 1 1/2 tablespoons lemon juice in skillet over medium heat. Dredge chicken in flour mixture. Place chicken in skillet; cook, turning to brown both sides, about 15 minutes. Remove chicken to a plate, and keep warm.
Pour vermouth into skillet, and scrape brown bits with a wooden spoon. Stir in garlic, 1/4 cup lemon juice, water, and capers. Cook until reduced by half.
