4 tablespoons unsalted butter
1 shallot, minced
3 cloves garlic, minced
Pinch of nutmeg
1/4 cup all purpose flour
1/2 cup heavy cream
1/2 cup milk
1/2 cup shredded Gruyere cheese
1/4 cup freshly grated Parmesan
Kosher salt and freshly ground black pepper, to taste
1 (16-ounce) package frozen chopped spinach, thawed and squeezed dry
- Melt butter in a large skillet over medium heat. Add shallot, garlic and nutmeg. Cook, stirring frequently, until shallots have become translucent, about 2-3 minutes.
- Whisk in flour until lightly browned, about 1-2 minutes. Gradually whisk in heavy cream and milk. Cook, whisking constantly, until the sauce has begun to thicken, about 5 minutes.
- Stir in cheeses until melted, about 1-2 minutes; season with salt and pepper, to taste.
- Stir in spinach until well combined, about 1 minute.
- Serve immediately.