Step 1

1 For the squash: Preheat the oven to 350 degrees

Step 2

2 Line a rimmed baking sheet with parchment paper

Step 3

3 Use a very sharp knife to split the squash in half lengthwise, then place the halves cut sides down on the baking sheet

Step 4

4 Bake (middle rack) for 45 minutes, or until just soft when pierced through the skin with a skewer

Step 5

5 Turn cut sides up, season lightly with salt and let cool while you prepare the remaining components

Step 6

6 For the glazed onions: Pour the oil into a large skillet over medium heat

Step 7

7 When it shimmers, add the onion and cook, tossing frequently, until it starts to soften, 5 minutes

Step 8

8 Stir in the vinegar and sugar, reduce the heat to medium-low and cook until the onions are soft and the syrup is sticky, 10 minutes

Step 9

9 Transfer to a small bowl, and rinse out the skillet

Step 10

10 For the rice: Combine the rice, chestnuts, apricots, nuts, lemon juice, sage, salt, black pepper, cayenne pepper and paprika in a large bowl, stirring until thoroughly incorporated

Step 11

11 Taste, and add more salt, as needed

Step 12

12 For the mushrooms: Set the rinsed-out skillet over medium heat and pour in the oil

Step 13

13 When it shimmers, add the mushrooms and garlic; cook for 5 minutes, stirring frequently, until the mushrooms soften, exude their liquid and it evaporates

Step 14

14 Remove from the heat and season lightly with salt and pepper

Step 15

15 To assemble, scoop out the fibrous matter and seeds from the squash and discard (or save the seeds for another use), then scoop out a 2-inch channel of flesh, chop or break it up, and mix it into the rice

Step 16

16 Spoon the cranberry sauce into one of the squash halves, spreading it thinly in the cavity

Step 17

17 Add enough of the rice mixture so it is slightly mounded, and rises above the edge of the squash; you can spoon any remaining rice on the squash's serving platter

Step 18

18 Next, layer in this order: the roasted peppers, the glazed onions, the mushrooms and sun-dried tomatoes

Step 19

19 Toss the spinach with the lemon juice, then scatter the leaves on top

Step 20

20 Place the other squash half on top, cut side down, lightly pressing if needed to help balance the roast

Step 21

21 Use skewers to secure it, or tie with kitchen twine in three evenly spaced spots

Step 22

22 Return to the oven and bake (350 degrees) for an additional 15 minutes, or until the filling is heated through

Step 23

23 Remove the skewers or twine

Step 24

24 Use a large serrated knife to cut the squash roast crosswise into 8 thick slices, or 12 thinner ones (depending on the appetite of your guests)

Step 25

25 Serve warm

Step 26

26 NOTE: To roast the bell peppers, position an oven rack 6 inches from the broiler element; preheat the broiler

Step 27

27 Line a baking sheet with aluminum foil

Step 28

28 Place the peppers on the baking sheet; broil until charred black on all sides, turning it with tongs as needed

Step 29

29 Transfer to a heat-proof bowl and cover with a plate to steam

Step 30

30 Once the peppers are cool enough to handle, rub off and discard the charred skins; also discard the stems and seeds