Spray a pan with cooking spray. Cut challah bread into bite-sized pieces. In a bowl, whisk eggs, whole milk, heavy cream, brown sugar, granulated sugar, ground cinnamon, and vanilla extract.
Add the pieces of bread to the mixture and toss until coated. Transfer to the baking dish. Beat cream cheese with egg, sugar, and vanilla until smooth.
Drizzle the cheesecake mixture over the top of the bread. Dot with raspberry preserves. Run a knife back and forth through the dish to swirl into the bread.
Bake in 350°F oven for 50-55 minutes. The center will be a touch jiggly and the edges should be golden brown.