In a large skillet, melt 3 tablespoons of unsalted butter over medium heat. Add the minced garlic and sauté for about 1-2 minutes, until fragrant but not browned.
Add the shrimp to the skillet. Cook for about 2-3 minutes on one side, then flip and cook for an additional 2-3 minutes, or until they turn pink and opaque. Remove the shrimp from the skillet and set aside.
In the same skillet, pour in the heavy whipping cream. Bring it to a gentle simmer, stirring occasionally. Add the grated Parmesan cheese, the remaining 4 tablespoons of butter, ground black pepper, salt, and a pinch of nutmeg. Stir until the cheese is melted and the sauce is smooth.
Toss in the baby spinach and stir until it wilts down into the creamy sauce.
Return the cooked shrimp to the skillet and stir to coat them in the sauce. Cook for an additional minute to heat everything through. Serve immediately over zucchini noodles or cauliflower rice for a complete meal.
