Ham and Potato Corn Chowder

Name: Ham and Potato Corn Chowder
Ingredients: 2 Stalks Celery (chopped); 2 C. Cooked ham (diced); 3 C. Milk; 6 Slices Bacon (cooked and crumbled); Salt and pepper to taste; 1 Onion (chopped); 5 ½ Tbsp. Butter (divided); ⅓ C. All purpose flour; 1 Bay leaf; ¾ tsp. Oregano; 5 Red onions (Medium, cubed); 2 Cans Chicken broth (14.5 oz. each); Green onions (chopped for garnish); 2 Carrots (peeled and diced); ½ tsp. Dried thyme; ½ C. Sour cream (or heavy whipping cream); 2 C. Corn (fresh or frozen)