To achieve crispy skin on roasted butternut squash, ensure the squash pieces are thoroughly dry, coated with enough oil, roasted at a high temperature of 400-425°F (200-220°C) in a single layer, and flipped halfway through cooking.
The key to crispy butternut squash skin lies in minimizing moisture and maximizing direct heat exposure. First, after washing and chopping your butternut squash (leaving the edible skin on), it's crucial to pat the pieces, especially the skin, completely dry with paper towels. Any residual moisture will cause the squash to steam rather than crisp. Next, toss the dry squash pieces with enough oil (such as olive or avocado oil) to lightly coat all surfaces; this fat helps conduct heat and promotes browning. Arrange the squash in a single layer on a baking sheet, ensuring there's ample space between each piece. Overcrowding traps steam and prevents crisping. Roast in a preheated oven at a high temperature, ideally between 400-425°F (200-220°C). Midway through the roasting time (typically after 15-20 minutes, depending on size), flip the squash pieces to ensure even browning and crisping on all sides. For an extra crisp result, consider letting the squash cook undisturbed for a longer period on one side before flipping.
For ultimate crispiness, preheat your baking sheet in the oven while it comes to temperature before adding the oiled squash.