Make Cajun spice mix.
It's preferable to do all cooking in a Dutch oven pot on the stove.
Cook 1 link of andouille sausage.
Remove sausage from pan, then cook diced chicken, seasoning it with Cajun spice mix, salt, and pepper.
Remove chicken from pan, then cook shrimp, seasoning it with Cajun spice mix, salt, and pepper.
Remove shrimp from pan, then cook onion, bell pepper, celery, and garlic (should be two parts onion, one part pepper, and one part celery, all diced).
Add chicken, sausage, and shrimp back to pan.
Add diced tomatoes, tomato paste, hot sauce, chicken broth, bay leaves, and more Cajun spice mix (to taste, take a spoon and taste the broth).
Cook covered (medium high ish) for 20ish minutes.
Top with green onion (and parsley if you like).