Instructions

1. Preheat oven to temperature indicated on puff pastry package. Place puff pastry in 1 layer on 1 or 2 parchment-lined baking sheets. Poke holes all over pastry with a fork. Cover each baking sheet with another piece of parchment and another baking sheet over top. Put a heavy ovensafe weight item (e.g. cast iron frying pan) on top of layered baking sheets. Bake according to suggested time on package, or until golden brown. Remove from oven and remove weight and top sheet pan. Allow to cool.
2. Once cool, cut sheets into twelve 2½ x 5-in (6.25 x 12 cm) rectangles. Set aside.
3. Set oven to 375 F (190 C). Toss squash in 3 tbsp (45 ml) olive oil, season with salt and pepper to taste, and add cinnamon and nutmeg. Transfer squash to a parchment-lined baking sheet and roast until cooked through and light golden on edges, about 20 minutes.
4. Fill a small saucepan with enough vegetable oil to fry mushrooms. Heat oil over medium-high heat to about 375 F (190 C). Fry mushrooms until golden brown and crisp (in batches, if necessary). Remove to paper towel to drain, and season with salt and pepper. Set aside.
5. In the same oil, fry sage leaves, a few at a time. Be careful, as they bubble up and may spit a bit. Remove to paper towel to drain, and season with salt and pepper.
6. In a medium frying pan, fry onion in butter and remaining 1 tbsp (15 ml) olive oil over medium heat until caramelized, about 15 to 20 minutes.
7. Season ricotta with 2 tsp (10 ml) salt and transfer to a piping bag with a large round tip (or use a plastic freezer bag with the corner cut off).
8. To assemble, lay 1 piece puff pastry on a dinner plate. Top with 1/12 of the squash, mushrooms, caramelized onions and hazelnuts, and repeat. Place third and final layer of pastry on top and garnish with ¼ of the sage leaves, celery leaves and radish.