Chunky Chicken Chowder

Name: Chunky Chicken Chowder
Ingredients: 4 chicken thighs, bone in, skin removed; Kosher salt and freshly ground black pepper; 4 tablespoons butter; 1 tablespoon vegetable oil; 1 large Vidalia or sweet onion, chopped; 10 to 12 thyme sprigs, in a bundle; 2 bay leaves; 4 cloves garlic, roughly chopped; 4 cups chicken stock; 2 russet potatoes, peeled and cut into bite-sized cubes; 8 ounces frozen white corn; 2 tablespoons all-purpose flour; 2 cups milk; 1 cup heavy cream; 1 lemon, halved for spritzing