Instructions: Preheat the Oven: Preheat your oven to 350°F (175°C). Grease and flour a 9-inch round cake pan.
2. Prepare the Batter: In a large mixing bowl, combine the all-purpose flour, 1 cup of granulated sugar, baking powder, baking soda, and salt.
3. Add Wet Ingredients: Beat in the eggs, one at a time, until well combined.Stir in the sour cream and vanilla extract until the batter is smooth.
4. Make Raspberry Filling: In a separate bowl, toss the fresh raspberries with 1/4 cup of granulated sugar and cornstarch until well coated.
5. Assemble the Cake: Spread the raspberry filling evenly over the batter.Spoon the remaining batter over the raspberry filling, smoothing the top with a spatula.
6.Bake and Serve: Bake in the preheated oven for 40-45 minutes, or until a toothpick inserted into the center comes out clean.Allow the cake to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.