Heat vegetable oil in a large skillet over medium heat.
Add the chopped onion, bell pepper, and celery; sauté until softened.
Stir in the garlic and Cajun seasoning; cook for 1-2 minutes.
Stir in the rice and toast for a few minutes, allowing it to absorb flavors.
Pour in the broth and bring to a simmer; cover and reduce heat.
Cook for about 15-20 minutes, or until rice is tender and broth is absorbed.
Add shrimp, stir gently, cover, and cook until shrimp are pink and opaque.
Remove from heat and let sit for 5 minutes before fluffing with a fork.
Garnish with fresh parsley and serve warm.