1. Preheat your oven to 375 F (190 C). Lightly grease a 9×13 inch baking dish or a similar oven-safe casserole dish.

2. Heat the olive oil in a large skillet or Dutch oven over medium heat. Add the chopped onion and cook until it softens and becomes translucent, about 3-4 minutes. Stir in the minced garlic and drained sun-dried tomatoes, cooking for another minute until fragrant.

3. Reduce the heat to low. Crumble the Boursin cheese into the skillet with the onion mixture. Stir gently until the cheese begins to melt and combine with the oil and aromatics. Gradually whisk in the chicken broth and heavy cream, stirring constantly until the sauce is smooth and creamy. Season with salt and black pepper to your taste.

4. Carefully add the uncooked potato gnocchi directly to the sauce in the skillet. Stir gently to ensure all the gnocchi are coated in the creamy sauce. Fold in the fresh spinach, stirring until it just begins to wilt into the hot sauce.

5. Pour the entire gnocchi and sauce mixture into your prepared baking dish, spreading it evenly. Sprinkle the grated Parmesan cheese over the top.

6. Bake in the preheated oven for 20-25 minutes, or until the sauce is bubbly, the gnocchi are tender, and the top is lightly golden brown.

7. Once out of the oven, let the bake rest for 5 minutes before serving. Garnish with fresh basil or parsley, if desired.