Very Lemony Chicken

1 1/2 lb chicken breast, skinned, fat removed
1/2 C fresh lemon juice
2 Tbsp white wine vinegar
1/2 C fresh lemon peel, sliced
3 tsp fresh oregano, chopped (or 1 tsp dried oregano, crushed)
1 medium onion, sliced
1/4 tsp salt
to taste black pepper
1/2 tsp paprika