In a medium pot, bring 4 cups of water to a boil. Slowly whisk in the grits, then reduce to a simmer. Cook for about 20–25 minutes, stirring occasionally, until the mixture is thick and creamy.
Once the grits are cooked, stir in the heavy cream and shredded cheddar cheese. Season with salt and pepper to taste. Keep warm on low heat.
In a large skillet over medium heat, add the chopped bacon. Cook until crispy, about 5-7 minutes. Remove the bacon from the skillet and set aside, leaving the drippings in the pan.
In the same skillet with the bacon drippings, add minced garlic and diced jalapeño (if using). Sauté for about 1 minute until fragrant.
Add the shrimp to the skillet and season with Cajun seasoning, salt, and pepper. Cook for 3-4 minutes, or until the shrimp are pink and opaque.
Add the cooked bacon back into the skillet. If desired, toss in a tablespoon of butter for extra richness.
To serve, spoon the cheesy grits onto plates or bowls, top with the sautéed shrimp mixture, and garnish with chopped green onions.
Serve immediately while hot. Each bowl is a wonderful combination of flavors that will leave everyone asking for more!