Coat bowl of slow cooker with nonstick
cooking spray. Place onion and garlic in
bottom of slow cooker. Season chicken on
both sides with Greek seasoning, thyme
and black pepper; arrange in bottom of
slow cooker. Drizzle lemon juice over
chicken and evenly spoon tomatoes and
olives on top.
Cover and cook on HIGH for 6 hours or
LOW for 8 hours. During last 30 minutes
of cooking time, stir in beans.
To serve, stir in oregano and spoon over
cooked orzo. Garnish with lemon slices.