Delightful Raspberry Cheesecake with Crumb Topping 

1. Prepare the crust: Preheat oven to 325°F (163°C). Mix graham cracker crumbs, melted butter, and sugar in a bowl. Press mixture into the bottom of a 9-inch springform pan. Bake for 10 minutes, then let cool.
2. Make the filling: Beat cream cheese and sugar until smooth. Add eggs one at a time, beating after each addition. Mix in vanilla and sour cream until well combined. Fold in fresh raspberries gently.
3. Assemble and bake: Pour cheesecake filling over the crust. In a separate bowl, combine flour and brown sugar, then cut in cold butter until mixture resembles coarse crumbs. Sprinkle crumb topping over the cheesecake.
4. Bake for 55-60 minutes, or until the center is set. Let cool to room temperature, then refrigerate for at least 4 hours before serving.