1. Prepare Grits: Bring 7 cups water to a boil in a 4-qt. saucepan over medium-high heat. Slowly whisk in grits; reduce heat to medium, and cook, whisking constantly, 5 minutes. Cover, reduce heat to low, and cook, stirring occasionally, 1 hour or until tender. Fold in cheese and 1/4 cup butter.
2. Prepare Shrimp Sauce: Peel shrimp; devein, if desired.
3. Cook bacon in a large skillet over medium-high heat, stirring often, 4 to 5 minutes or until crisp; remove bacon, and drain on paper towels, reserving 2 Tbsp. drippings in skillet.
4. Melt 6 Tbsp. butter in hot drippings in skillet. Reduce heat. Add onion, poblano pepper, and garlic; sauté 2 minutes or until onion is translucent. Add shrimp; cook, stirring often, 1 to 2 minutes. Add salt and next 2 ingredients; toss to coat.
5. Sprinkle flour over shrimp mixture; toss. Add broth and next 2 ingredients. Cook just until shrimp turn pink, stirring to loosen particles from skillet. Stir in bacon and parsley. Serve over grits with green onion.