Spray a 9x13-inch baking pan with nonstick spray.
Arrange the bread in a tight, flat layer in the prepared baking pan. The bread should be as close together as possible.
18 ounces French bread
In a small bowl, mix the brown sugar and cinnamon together. Set aside.
½ cup dark brown sugar, ½ teaspoon ground cinnamon
In a large bowl, whisk the egg whites with milk, sugar, and vanilla until blended; pour over the bread.
1½ cups egg whites, 2 cups skim or almond milk, ¼ cup granulated sugar, 1 teaspoon pure vanilla extract
Arrange the peaches on top of the bread and sprinkle with the brown sugar and cinnamon.
38 ounces no sugar added sliced peaches
Cover tightly and refrigerate for at least 8 hours.
Remove baking dish from refrigerator 30 minutes before baking. Preheat the oven to 350°F.
Pour the cream into a small pan set over high heat and bring to a boil. Reduce to low heat and simmer until reduced by half, about 10-12 minutes.
1 cup heavy cream
Drizzle sauce over peaches, place the pan in the oven, and bake, uncovered, until casserole is lightly browned on top and just cooked through, 50-55 minutes.
Let stand for 10 minutes before serving.
Serve with whipped topping if you're feeling sassy!
1 cup whipped topping