1 tablespoon canola oil
1/2 pound smoked sausage, sliced into 1/4-in.-thick rounds (1 3/4 cups slices)
1 pound boneless, skinless chicken thighs (about 4), cut into 1-in. pieces (1 1/2 cups pieces)
2 1/2 teaspoons Cajun seasoning (such as Slap Ya Mama), divided
3/4 cup chopped yellow onion (from 1 medium onion)
1/2 cup chopped celery (from 1 large stalk)
1/2 cup chopped green bell pepper (from 1 small bell pepper)
1/2 cup chopped red bell pepper (from 1 small bell pepper)
2 teaspoons minced garlic (from 1 large garlic clove)
3 cups chicken broth
1 (14.5-oz.) can diced tomatoes
2 cups uncooked long-grain rice
2 dried bay leaves
1 tablespoon fresh thyme leaves
1 pound medium peeled, deveined raw shrimp
1/2 teaspoon smoked paprika
1/4 teaspoon kosher salt
1/4 teaspoon black pepper
2 tablespoons chopped fresh flat-leaf parsley
Chopped scallions