This salad combines crisp chicory with slices of oven-roasted acorn squash. A kiss of maple syrup draws out the natural sweetness of the squash. An aromatic hazelnut vinaigrette can be drizzled over the dish.
Preheat oven to 375 degrees. Toss squash with 1 tablespoon oil and the syrup, and season with salt and pepper. Arrange on a rimmed baking sheet. Roast, flipping once, until golden brown and tender, about 20 minutes; set aside.
Whisk vinegar, lemon juice, and 1/4 teaspoon salt in a bowl. Pour in remaining 6 tablespoons oil in a slow, steady stream, whisking. Season with pepper.
Just before serving, toss greens and squash with dressing, and arrange on a platter. Sprinkle with hazelnuts.
Dress greens just before serving so they won't wilt, or offer the dressing on the side.