My take on a recipe from Melissa Clark in the New York Times

INGREDIENTS:

• 4 garlic cloves

• 1 cup heavy cream

• 2 thyme branches

• 2 tablespoons finely chopped fresh sage

• 1 tablespoon extra-virgin olive oil, more as needed

• 1 pound ground lean beef

• ¾ teaspoon kosher salt, more as needed

• Black pepper, as needed

• 1 cup finely chopped onion

• 3 ounces baby spinach (3 packed cups)

• 2 teaspoons Worcestershire sauce

• 1 pound russet potatoes (*)

• 6 ounces Gruyère, grated (1 1/2 cups).    

METHOD:


1. Peel the garlic cloves and chop very finely

2. Strip the leaves from the thyme sprigs.

3. In a small pot over medium heat, combine cream, half of the chopped garlic, the thyme leaves and 1/2 tablespoon sage.

4. Bring to a simmer; cook until reduced to 1/2 cup, about 30 minutes.

5. Heat the oven to 350 deg F.

6. While cream is simmering peel potatoes and cut into rounds -- 1/4-inch-thick at most.

7. Heat oil in an ovenproof 10-inch skillet (preferably cast iron) over medium-high heat.

8. Brown the beef well, crumbling with the spatula as it cooks.

9. Season with 1/4 teaspoon salt and a few grinds of pepper; transfer meat to a paper-towel-lined plate.

10. Add the onion to the pan drippings adding olive oil if the pan seems dry.

11. Cook, stirring occasionally, until onions are tender and golden, about 10 minutes.

12. Meanwhile remove the thicker stems from the spinach and discard.

13. Julienne the spinach leaves.

14. When the onion is cooked, add the remaining chopped garlic and sage to the pan and stir.

15. Return the meat to the skillet.

16. Toss in the spinach and stir in until wilted.

17. Season with 1/4 teaspoon salt, the Worcestershire sauce and pepper to taste.

18. Layer half the potato slices over the meat mixture with the slices slightly overlapping to form a spiral that covers the surface. (if you are using rutabaga or sweet potatoes as well, alternate these with the potatoes.)

19. Season lightly with salt and pepper;

20. Top with half the cheese.

21. Repeat the layering with the remaining potatoes and cheese.

22. Spoon reduced cream evenly over top.

23. Cover pan tightly with foil and bake until vegetables are very tender, 50 to 65 minutes. (Check the underneath layer of potatoes with the tip of a sharp knife. They should be tender.) if the potatoes were sliced very thinly the cooking time may be reduced.

24. Uncover and cook until golden brown, about 10 minutes more.

25. Cool 10 minutes before serving.

(*)   Ms Clark's recipe called for ½ lb potatoes and ½ lb rutabaga.       I'm not all that keen on rutabaga so used only potatoes.    Someone commented that they had used sweet potatoes instead of rutabaga.     Whatever you choose is fine, but do slice each thinly -- no more than 1/4 inch.      Also see the notes on step 18 of the method.