To make the crumb topping, combine flour, sugar and cinnamon in a small bowl. Add cold butter and toss to coat, using your fingers to work the butter into the dry ingredients until it resembles coarse crumbs; set aside.
Lightly coat the inside of a 6-qt slow cooker with nonstick spray.
In a large glass measuring cup or another bowl, whisk together milk, pumpkin, eggs, pumpkin pie spice and vanilla.
Place a layer of bread cubes evenly into the slow cooker. Pour pumpkin mixture evenly over the bread cubes.
Sprinkle the crumb topping evenly over the bread cubes.
Cover and cook on low heat for 3-4 hours or high for 1-2 hours.
To make the cream cheese glaze, combine cream cheese, confectioners’ sugar, milk and vanilla in a small bowl until smooth.
Serve immediately, drizzled with cream cheese glaze and garnished with confectioners’ sugar and pecans, if desired.