Add 1 1/2 cups white rice to a medium saucepan with 2 1/4 cups water. Bring to a boil over medium-high heat. Once bubbling, cover and reduce the heat to low. Cook for 15 minutes. Remove from the heat and let rest for 15 minutes with the lid on.
While the rice cooks, bring 4 cups low-sodium vegetable stock and 2 cups water to a boil in a large pot. Add 6 cups cauliflower and boil for about 10 minutes, until tender. Use a slotted spoon to transfer the cauliflower pieces to a blender (or food processor).
Don't drain the pot yet. You might need extra liquid for the next step.
Cover the blender and puree the cauliflower, adding 1/2 cup 2% milk (and reserved cooking liquid as needed) until the cauliflower has a smooth, creamy consistency. Season with 1 teaspoon salt. Pour the cauliflower puree over the cooked rice and stir to combine. Set aside.
Place a large nonstick skillet over low heat. Melt 2 tablespoons butter and add 8 cloves garlic and cook, stirring frequently, for about 3-5 minutes until the garlic is very fragrant. Add the rice mixture and stir everything together. Add 1/2 cup mozzarella cheese and stir until it has melted into the rice. Season with additional salt and pepper to taste. Set aside.
Stuffed Peppers
Preheat your oven to 400 degrees F.
In a large skillet over medium-high heat, melt 1 tablespoon butter. Add 1 pound raw shrimp and 2 cloves garlic, and cook for 3 to 4 minutes until the shrimp begins to turn pink. Flip the shrimp over and cook for another 2 to 3 minutes on the other side until fully cooked. Remove from the skillet and let cool slightly before rough-chopping shrimp. Return to the skillet.
Add the cheesy rice to the shrimp along with 1/2 cup mozzarella cheese. Stir to combine cooking until the cheese has melted.
Place the prepared 4 large bell peppers in a 9x13 baking dish (or on a rimmed baking sheet), with the cavity facing up. Sprinkle the peppers liberally with salt. Fill each pepper half with the rice and shrimp mixture, dividing evenly between them.
Bake for 15 minutes. Carefully sprinkle 1/2 cup cheddar cheese on top of the peppers. Bake for another 10 minutes, until the peppers are soft and the cheese has melted.
Remove from the oven and sprinkle with chopped fresh parsley for garnish. Serve warm.
Notes
The cauliflower head should be 2-2.5 pounds to yield 6 cups of chopped cauliflower. If you prefer, you can use prepared florets instead. You will need 20-24 ounces of florets.
You can use all the same color bell peppers or use a combination for extra color. I usually grab whichever ones are on sale.
Pat the thawed shrimp dry before cooking.
Cook shrimp just until pink before baking, so they stay tender.
If your bell peppers are on the smaller side, you may have extra filling. Bake it in a small ramekin alongside the peppers.