In a large pot of salted boiling water, cook the potato gnocchi according to package instructions until they float to the surface. This usually takes about 2-3 minutes. Drain and set aside.
In a large skillet, melt the butter over medium heat. Add the minced garlic and sauté for about 1 minute until fragrant, being careful not to brown it.
Add the chopped spinach to the skillet and cook for 2-3 minutes until it wilts down significantly.
Pour in the heavy cream, stirring to combine. Then, add the onion powder, nutmeg, salt, and pepper. Let it simmer for about 2-3 minutes until slightly thickened.
Gradually stir in the grated Parmesan cheese until fully melted and incorporated into the sauce. Adjust seasoning as necessary.
Toss the cooked gnocchi in the creamy spinach sauce, ensuring each piece is well-coated. Allow it to cook together for an additional 2 minutes to let the flavors meld.
Remove from heat and serve immediately, garnished with fresh basil leaves.