In a large skillet, heat the olive oil over medium heat. Add the diced onion, bell pepper, and celery. Sauté for about 5 minutes until the vegetables are softened.
Stir in the minced garlic and cook for an additional minute until fragrant.
Add the shrimp to the skillet and cook for about 3-4 minutes until they turn pink and opaque. Remove the shrimp from the skillet and set aside.
In the same skillet, add the rice and stir to coat it with the vegetable mixture. Cook for 2 minutes, allowing the rice to toast slightly.
Pour in the chicken broth, Worcestershire sauce, Cajun seasoning, thyme, black pepper, and salt. Stir to combine and bring to a boil.
Reduce the heat to low, cover the skillet, and let it simmer for 18-20 minutes or until the rice is cooked and has absorbed the liquid.
Once the rice is done, gently fold the cooked shrimp back into the skillet. Cover and let it sit for an additional 5 minutes to allow the flavors to meld.
Fluff the rice with a fork and garnish with sliced green onions before serving.