In a medium saucepan, bring 4 cups of water and 1 teaspoon of salt to a boil. Gradually whisk in the grits, reduce heat to low, and simmer for about 20-25 minutes, stirring occasionally until thickened.
Once the grits are cooked, stir in the cheddar cheese and 2 tablespoons of butter until melted and creamy. Keep warm.
In a large skillet over medium heat, cook the chopped bacon until crispy. Remove the bacon and set aside, leaving the drippings in the skillet.
In the same skillet, add the minced garlic and sauté for about 30 seconds until fragrant.
Add the shrimp to the skillet and season with paprika, black pepper, and cayenne pepper (if using). Cook for 3-4 minutes or until the shrimp are pink and opaque.
Stir the cooked bacon back into the skillet with the shrimp and mix well.
To serve, spoon the cheesy grits onto plates and top with the shrimp and bacon mixture. Garnish with sliced green onions and serve with lemon wedges on the side.