- Make the cheese grits: In a medium saucepan over high heat, bring 4½ cups water to a boil. Whisk in grits and salt and reduce heat to low. Cook, stirring occasionally, until grits are thickened, approximately 35 to 40 minutes. Remove from heat and add cheeses, butter, pepper, and Tabasco. Adjust seasoning to taste.
- Meanwhile, in a medium skillet over medium-high heat, cook bacon, stirring occasionally, until crisp, approximately 5 to 6 minutes. Drain bacon on paper towels, reserving fat in pan and adding peanut oil as needed for approximately 11⁄2 tablespoons of fat. Set aside.
- Toss shrimp in flour until lightly coated, shaking off any excess. Place shrimp in pan over medium-high heat and cook on one side. When shrimp start to turn pink, flip them and add mushrooms and bacon. Cook for about 2 minutes.
- Add garlic, stirring constantly to keep it from browning. Remove from heat and add lemon juice, Tabasco, and green onions. Spoon over cheese grits and serve immediately.