Slow-cooker Greek Chicken with Tzatziki Sauce

I was looking for a new slow cooker recipe and this one for Greek chicken with tzatziki sauce is a keeper!  It's based on a recipe I found online, but as usual I changed it up just a bit.  

Ingredients for Chicken

• 2 lb boneless skinless chicken breast
• 1 onion chopped (I used a sweet yellow, but you could use basically any kind, I think)
• 1 tsp. (2 cloves) garlic, minced
• 1 tsp dried oregano 
• 1/2 tsp salt
• 1/2 tsp pepper
• 3 Tbsp olive oil
• 1 Tbsp red wine vinegar
• Juice of 1/2 medium lemon
• 1/3 cup water

Ingredients for Tzatziki Sauce:

• 2 cups plain, fat free greek yogurt
• 1 cucumber, finely grated
• 1 1/2 tsp (2 to 3 cloves) garlic, minced 
• 1 Tablespoon white wine vinegar
• 1 teaspoon dried dill 
• 1 teaspoon dried oregano 
• Salt and pepper to taste
• Juice of 1/2 medium lemon
• 1 tablespoon extra-virgin olive oil

Options for serving accompaniments:

• warm pita bread
• red bell pepper
• romaine lettuce or spinach
• cucumber 
• tomatoes
• feta cheese crumbles
• kalamata olives
• On top of a salad

Instructions

1. Spay slow cooker container with cooking spray. 
2. Add the chicken at bottom of the slow cooker. 
3. In a small bowl combine onion, garlic, oregano, salt, pepper, olive oil, red wine vinegar, lemon juice, and water. Pour over chicken. 
4. Cook on low for 6-8 hours or high for 4-6.
5. Shred or chunk chicken.  
6. Make the sauce: In a medium bowl combine all sauce ingredients. Refrigerate for 30 minutes to let the flavors blend.
7. Prepare chicken on warm greek pita bread with desired veggies and sauce on top.  Or make a salad, top with chicken, and use sauce as dressing.