2 potatoes, peeled and cubed
3 tablespoons butter
1/2 cup chopped sweet onion (such as Vidalia(r))
3 tablespoons all-purpose flour
1 tablespoon chicken bouillon granules
1/2 teaspoon ground black pepper
1/4 teaspoon dried thyme
3 cups milk
1 (16 ounce) package frozen mixed vegetables
2 cups cubed cooked ham