Position a rack in the top third of the oven and preheat to 425 degrees F. Toss the squash with the olive oil, maple syrup, 1/2 teaspoon salt and a few grinds of pepper in a large bowl. Wrap half a slice of prosciutto around each squash wedge and arrange on a baking sheet.
Roast until the prosciutto begins to soften and the squash is almost tender, about 15 minutes. Flip the squash and continue cooking until the prosciutto is browned and the squash is tender, 7 to 14 more minutes. Transfer to a platter.
Drizzle the butternut squash with balsamic vinegar and top with basil. Serve warm or at room temperature.
Photograph by Levi Brown