3 tablespoons butter, divided
1/2 cup diced onion
1/2 cup diced carrot
1/2 cup diced celery
3 tablespoons flour
1 cup chicken broth
1 cup milk
1 cup sour cream
1 (2 oz) jar pimientos, drained
1 lb cooked chicken, diced or shredded
1 cup shredded cheddar cheese, divided
1 cup flour
1/2 tablespoon baking powder
1 1/2 teaspoons sugar
1/2 teaspoon salt
1/4 teaspoon baking soda
2 tablespoons unsalted butter
3/4 cup buttermilk
flour, for rolling
1 tablespoon melted butter