Heat oven to 450° F. Toss the squash, oil, ½ teaspoon salt, and ¼ teaspoon pepper on a rimmed baking sheet and roast, tossing once until tender, 16 to 18 minutes.
Meanwhile, combine the vinegar and honey in a small pot over medium heat and cook, stirring occasionally, until syrupy, 8 to 10 minutes. Let cool.
Top the bread with the ricotta and roasted squash, dividing evenly. Drizzle with the syrup.