Prep the Swiss Chard

1. Slice the stems off the leaves and reserve them for another part of the recipe.
2. Rinse the leaves thoroughly and pat dry with a towel, then set them out to finish air-drying while continuing with the recipe.

Roast the vegetables

1. Preheat the oven to 400°F. Set the butternut squash in the oven for 5 minutes to soften the skin. Peel the squash, then cut off the bulb end and set aside or reserve for another use. Trim the rounded edges of the neck, then split it lengthwise, leaving two rectangular slabs of butternut.
2. Coat the butternut with a few teaspoons of olive oil and season with a few pinches of salt, pepper, cinnamon, and nutmeg, and set on a sheet pan.
3. Trim the top and bottom off the red bell pepper, set aside or reserve for another use, then split it down the side. Lay the wide strip of pepper on the cutting board with the inside facing up. Trim off all of the white membrane and remove all seeds. Cut into two or three pieces if needed to lie flat.
4. Coat the bell pepper pieces with a splash of olive oil, season with a pinch of salt, and set on a sheet pan.
5. Roast in the oven for 30 to 40 minutes. Remove the bell pepper skin when it is cool enough to handle and set both aside until it's time to assemble the Wellington.

Make the duxelles

1. Warm a large nonstick skillet over medium-high heat and add 1 tablespoon each of butter and olive oil.
2. Finely chop the mushrooms. Save time by pulsing in a food processor
3. Add 1/2 cup of minced onions to the pan and cook for 5-7 minutes. Then, add the mushrooms, garlic, parsley, and 1 teaspoon each of salt and pepper.
4. Cook until the mushrooms have released all their moisture, and that moisture has evaporated. Then, deglaze with the wine.
5. Cook until the wine has evaporated; then, taste and adjust the salt as needed. Set aside until it's time to assemble the Wellington.

Make the vegetable stuffing mix

1. Using the same nonstick skillet, melt 1 tablespoon each of butter and olive oil over medium-high heat.
2. Add the cauliflower, onion, celery, and carrots, and saute for 10 minutes.
3. Next, add the minced garlic, fresh herbs, 1/2 teaspoon of each salt and pepper, and continue cooking until the vegetables are tender.
4. Stir in the torn bread pieces and toss to coat in the oil and vegetables. Taste for salt, then set aside.

Mold the layers in a loaf pan

1. Using the loaf pan as a guide, set a piece of plastic wrap down that is long enough to fit inside the pan with the sides hanging over.
2. Start by laying the Swiss chard leaves across the plastic wrap, then add a long leaf on either end to wrap the sides.
3. Next, spread 2/3 of the duxelle mixture over the leaves, then lay the red pepper slices on top, filling the space.
4. Top the red peppers with the vegetable stuffing mixture, packing it into a rectangle.
5. Carefully lift the sides and edges of the plastic wrap and place the partial structure into the loaf pan, patting it down and into the corners and draping the plastic and chard leaves over the sides of the pan.
6. Next, add the butternut squash slabs to the loaf pan, trimming them to cover completely, and top with the remaining duxelle mix.
7. Cover the duxelle with one more chard leaf, tucking it into the edges and pulling any leaf layers over the top. Cover the loaf with plastic wrap and weigh it down with something heavy, such as a few cans of beans. Chill the loaf for at least 2 hours to allow it to firm up before wrapping in pastry.

Assemble the Vegetable Wellington

1. Prepare a sheet pan with parchment or a silicone mat and set aside.
2. Lay one sheet of puff pastry on a floured surface and roll it out slightly more. (Optional) Brush with Dijon mustard before placing the loaf.
3. Unwrap the chilled loaf and set it on the pastry with the stuffing side down.
4. Pull the long sides of the puff pastry up and press the edges together, brushing the inside with egg wash to help with adhesion.
5. On the ends, pull the sides in and press together to adhere, trimming off any excess pastry to help it lay flatter. If needed, patch pastry seams with trimmed dough, sealing with egg wash.
6. Brush the bottom of the pastry with egg wash before flipping it onto the parchment-lined sheet pan, then brush the top with the egg wash.
7. Refrigerate for at least an hour before baking. If you can't bake it until the next day, don't egg wash it yet, and wrap it tightly with plastic wrap.

Baking the Wellington

1. Heat the oven to 425°F. Bake the Wellington straight from the refrigerator, for 20 minutes, then reduce the oven to 375°F and continue cooking for 40-50 minutes, or until the pastry is golden and the inside of the loaf reaches 160-185°F. Tent with foil if the top of the loaf gets too dark. Rest for 20 minutes before slicing for service.