In a large pot over medium heat, melt 2 tablespoons of butter. Once melted, add 1 cup of diced carrots, 1 cup of diced celery, and 1 cup of chopped onion, stirring occasionally until softened and fragrant, about 5-7 minutes. Add 3 minced garlic cloves, cooking for an additional minute until aromatic.

Season the sautéed vegetables with salt and pepper to taste. Pour in 8 cups of chicken stock, followed by 1 teaspoon of dried oregano and ½ teaspoon of celery seed. Add 1 pound of boneless skinless chicken breasts to the pot. Bring the mixture to a gentle boil over medium-high heat, then reduce to medium-low and cover.

Allow the chicken to simmer in the broth for 20 minutes, or until fully cooked and the internal temperature reaches 165°F. Once cooked, carefully remove the chicken from the pot and let it cool for a few minutes. Use two forks to shred the chicken into bite-sized pieces, then set aside.

Bring the soup back to a boil over medium-high heat. Stir in 1 cup of dried orzo pasta, cooking for 8-10 minutes until the orzo is al dente. Stir occasionally to prevent sticking.

After the orzo is cooked, return the shredded chicken to the pot. Add the zest of 1 lemon, the juice of 1 lemon, 1 cup of whole milk, and ½ cup of light cream. Stir in ¼ cup of freshly chopped dill, heating through for another 2-3 minutes while tasting for seasoning.