Step 1: Prepare the Vegetables and Chicken Dice onion, celery, and carrots into uniform 1/4-inch pieces for even cooking. Peel and cube potatoes into 1/2-inch pieces. If using raw chicken breasts, season with salt and pepper, then poach in simmering water for 12-15 minutes until cooked through. Shred or dice into bite-sized pieces. Using rotisserie chicken saves significant time and adds extra flavor.

Step 2: Create the Roux Base Melt 3 tablespoons butter in a large pot or Dutch oven over medium heat. Add diced onion, celery, and carrots, sautéing for 5-6 minutes until vegetables soften and onions turn translucent. Add minced garlic and cook for 30 seconds until fragrant, stirring constantly to prevent burning.

Step 3: Build the Creamy Base Sprinkle 1/3 cup flour over the sautéed vegetables, stirring constantly for 2 minutes to cook out the raw flour taste and create a golden roux. This creates the soup’s signature thick, velvety texture. Gradually add chicken broth while whisking continuously to prevent lumps from forming. Add broth in three separate additions, whisking until smooth after each pour.

Step 4: Add Liquid and Seasonings Once broth is fully incorporated and smooth, add whole milk, heavy cream, fresh thyme, bay leaf, poultry seasoning, and garlic powder. Stir well to combine all ingredients evenly. Bring the mixture to a gentle simmer over medium heat, stirring occasionally to prevent scorching on the bottom.

Step 5: Cook the Potatoes Add diced potatoes to the simmering soup. Cook for 10-12 minutes, stirring occasionally, until potatoes are fork-tender but still hold their shape. The potatoes will also help naturally thicken the soup as they release starch during cooking.

Step 6: Add Chicken and Final Vegetables Stir in cooked shredded chicken, frozen peas, frozen corn, and green beans if using. Cook for 3-4 minutes until vegetables are heated through and chicken is warmed. Remove bay leaf and discard. Taste and adjust seasoning with salt and black pepper as needed.

Step 7: Serve with Toppings Ladle the hot soup into bowls. Top each serving with crispy puff pastry croutons or oyster crackers for that essential pot pie crunch. Garnish with fresh parsley and thyme sprigs. Serve immediately while piping hot.