-Place racks in top and bottom thirds of oven; preheat to 400°F.

-Line a rimmed baking sheet with foil.

-Peel, de-seed and chop 1 delicata squash into ¾ inch cubes.

-Toss squash with 2 TBS olive oil in a medium bowl; season to taste with salt and pepper.

-Spread out squash on prepared sheet and roast, turning occasionally, until tender and golden in spots, 18–20 minutes.

-Meanwhile, spread out 1 cup whole hazelnuts on a baking sheet and toast in oven until beginning to turn golden brown, 7-9 minutes. Let cool on sheet.

-Chop the hazelnut nuts and place them in a small bowl.

-Whisk in 1/3 cup olive oil, ½ cup hazelnut oil, ½ cup sherry vinegar and 2 tsp sugar.

-Season vinaigrette to taste with salt and pepper.

-Take the stems off of 1 bunch of mustard greens and chop the leaves into thin strips.

-Place roasted squash and mustard greens in a large bowl; toss to combine.

-Drizzle vinaigrette over and season with salt and pepper; toss to coat.