Butternut Squash Casserole

Name: Butternut Squash Casserole
Ingredients: 2 (2 pound) butternut squash, halved lengthwise and seeded; 1 tablespoon extra-virgin olive oil; ½ cup old-fashioned rolled oats (see Tip); ½ cup chopped pecans; ¾ cup light brown sugar, divided; ¼ cup unsalted butter, melted, divided; ½ cup whole milk; 2 large eggs, lightly beaten; 1 teaspoon cornstarch; 1 teaspoon salt; ½ teaspoon ground cinnamon