Add 1 tablespoon olive oil to a large skillet and place over high heat. Add chicken pieces and season with salt and pepper. Brown the meat for about 5-6 minutes. Transfer to a large slow cooker.

Add chicken broth, dry white wine, worcestershire sauce, balsamic vinegar, thyme, rosemary, dried oregano, salt, and pepper to the slow cooker. Stir to combine.

Add garlic, onion, carrots, and diced potatoes to the slow cooker. Cover and cook on low for 7-8 hours or on high for 4-5 hours.

Remove 1/2 cup of chicken broth from the slow cooker and transfer to a medium bowl. Stir in ½ cup of milk and whisk in ¼ cup flour until smooth. Add back to the slow cooker and stir to combine.

Stir in frozen peas and cook uncovered on HIGH for 15-20 more minutes until the stew thickens. Taste and adjust seasoning with salt and pepper as necessary.