In a large skillet, heat olive oil over medium heat. Add sliced andouille sausage and cook until browned on edges, about 5-7 minutes. Remove sausage and set aside.
In the same skillet, add chopped onion, bell pepper, and minced garlic. Sauté for about 3-4 minutes until the vegetables are softened.
Stir in the Cajun seasoning, smoked paprika, dried oregano, cayenne pepper, salt, and pepper. Mix well until the vegetables are coated with the spices.
Add the long-grain rice to the skillet, stirring to combine with the vegetable mixture. Toast the rice for about 2 minutes, allowing it to absorb the flavors.
Pour in the chicken broth and drained diced tomatoes. Bring the mixture to a gentle boil.
Once boiling, reduce the heat to low, cover the skillet, and let it simmer for about 15-20 minutes, or until the rice is cooked and liquid is absorbed.
After the cooking time, remove from heat and fluff the rice with a fork. Add the reserved sausage back to the skillet, mixing everything together.
Taste and adjust seasoning if needed. Garnish with chopped green onions and fresh parsley before serving.