Season the shrimp: Pat shrimp dry with paper towels. In a bowl, toss with 1 teaspoon of the Cajun seasoning, smoked paprika, garlic powder, onion powder, cayenne (if using), and a pinch of salt and pepper. Set aside.

Heat the pan: Warm 1 tablespoon oil in a large skillet over medium-high heat until it shimmers.

Cook the shrimp: Add shrimp in a single layer. Cook 1–2 minutes per side, just until pink and opaque. Transfer to a plate. Do not overcook.

Sauté aromatics: Lower heat to medium. Add remaining 1 tablespoon oil and the butter. Stir in onion and bell pepper with a pinch of salt. Cook 3–4 minutes, until softened. Add garlic and cook 30 seconds, until fragrant.

Add cauliflower rice: Stir in the riced cauliflower and remaining Cajun seasoning. Cook 3–5 minutes, stirring often, until tender but not mushy.

Deglaze and steam: Pour in the broth to loosen browned bits and add moisture. Simmer 1–2 minutes until mostly absorbed.

Finish with freshness: Return shrimp to the pan. Add lemon juice, half the green onions, and half the parsley. Toss to combine. Taste and adjust seasoning with more Cajun spice, salt, or pepper.

Serve: Plate the cauliflower rice and top with shrimp. Garnish with remaining green onions and parsley. Serve with lemon wedges.