Preheat the oven to 400°F (205°C). Line a rimmed baking sheet with aluminum foil or parchment paper.

On the prepared baking sheet, combine the cauliflower rice, 1 tablespoon of the olive oil, 1½ teaspoons of the Creole seasoning, 1/2 teaspoon salt, and 1/4 teaspoon black pepper. Toss to evenly distribute, then roast, tossing occasionally, until the cauliflower rice is dry and a bit crispy-edged, about 12 minutes.

Meanwhile, season the chicken pieces evenly with 1-1/2 teaspoons of the creole seasoning, 1/2 teaspoon salt, and 1/4 teaspoon pepper.

In a 4 to 6-quart pot oven over medium-high heat, heat 1 tablespoon of the olive oil. When hot, add the chicken and cook, turning frequently, until browned on all sides, 5 to 6 minutes total. Remove the chicken to a plate. Reduce the heat to medium and add the celery, peppers, and sausage. Cook, stirring occasionally, until the vegetables are softened and the sausage is seared in places, 4 to 5 minutes.

Add the tomato paste and the remaining 1 tablespoon Creole seasoning, and toss to combine. Add 1/2 cup of water and scrape up any bits from the bottom of the pan. Let the mixture come to a simmer and thicken up a little, 2 to 3 minutes.