Instructions

1. Preheat the oven to 425 degrees Fahrenheit.
2. Heat 1/4 cup of extra-virgin olive oil in a large high-sided skillet or Dutch oven over medium-high heat.
3. Add 2 1/2 pounds of trimmed and halved Brussels sprouts to the skillet and cook, stirring occasionally, until they are charred in some spots, about 5 to 7 minutes.
4. Add 3 medium leeks (white and pale green parts, trimmed, halved lengthwise and coarsely chopped) and 6 thinly sliced garlic cloves to the skillet.
5. Cook, stirring, until the leeks and garlic have softened but have not taken on too much color, about 3 minutes.
6. Reduce the heat to medium and pour in 2 cups of heavy cream.
7. Cook, stirring occasionally, until the cream has reduced by half and is thick enough to coat the Brussels sprouts, about 8 to 10 minutes.
8. Stir in 1 tablespoon of lemon zest, then season with salt and freshly ground black pepper to taste. Adjust seasoning to ensure the Brussels sprouts are deeply flavored before baking.
9. Remove the skillet from heat and transfer the Brussels sprouts mixture to a shallow 2-quart baking dish.
10. Note: This mixture can be covered and refrigerated up to 1 day ahead. Bring to room temperature before proceeding.
11. In a medium bowl, combine 1 cup of coarse fresh or dried bread crumbs (or panko bread crumbs), 1/2 cup finely chopped parsley, and the remaining 1/4 cup of extra-virgin olive oil.
12. Season the bread crumb mixture with salt and freshly ground black pepper.
13. Scatter the bread crumb mixture evenly over the Brussels sprouts in the baking dish.
14. Place the baking dish in the preheated oven and bake uncovered until the top is golden brown and crisp, about 15 to 18 minutes.
15. Remove from the oven and let cool for a few minutes before serving.