In a small saucepan, bring water and sea salt to a boil.
Whisk in the stone-ground grits, reduce heat to low, cover, and simmer for 15-20 minutes until creamy and tender.
While grits cook, toss the shrimp in a bowl with Cajun seasoning and black pepper until evenly coated.
Heat olive oil in a large skillet over medium-high heat.
Add the diced bell pepper, onion, and celery to the skillet, sautéing for 4-5 minutes until the vegetables are softened and fragrant.
Push the vegetables to the side and add the shrimp to the skillet, searing for 2 minutes per side until pink and opaque.
Divide the warm grits into a bowl and top with the Cajun shrimp and sautéed vegetable mixture.
Garnish with fresh parsley before serving.