1-First Step: Make the raspberry jam Start by adding 3 cups fresh raspberries, 1/2 cup granulated sugar, and 1 tbsp lemon juice to a medium saucepan. Set the pan over medium heat and let the berries cook down slowly, stirring often. As they soften, mash them with a spoon or potato masher so the juices release and the mixture becomes saucy. In a small bowl, stir together 2 tsp cornstarch and 1 tbsp water to make a smooth slurry. Pour this into the bubbling raspberry mixture and continue cooking for a few more minutes until the jam thickens. If you want a smoother filling, strain the mixture through a fine mesh sieve to remove the seeds, then let it cool completely before using it.

2-Second Step: Mix the cheesecake filling In a bowl, beat 1/2 cup softened cream cheese with 1/3 cup powdered sugar until the mixture looks smooth and fluffy. This step matters because lumps in the filling can show up after baking. Add 2 tbsp flour, 1 large egg yolk, and 1/3 cup cooled raspberry jam, then mix just until combined. Set the filling aside while you prepare the chocolate batter. It should be thick enough to spoon into the pan without running all over the place. If the jam is too warm, the filling can loosen too much, so make sure it has cooled all the way.

3-Third Step: Prepare the pan and heat the oven Preheat your oven to 350°F, or 325°F if you are using convection. Thoroughly grease and flour a 10-cup bundt pan, getting into every ridge and curve. This part takes a little patience, but it helps the cake release cleanly later. If you have had bundt cakes stick before, be extra careful around the center tube and decorative grooves. A well-coated pan makes a big difference, especially with a cake that has a cheesecake layer in the middle.

4-Fourth Step: Whisk the dry ingredients In a large bowl, whisk together 2 cups all-purpose flour, 2/3 cup cocoa powder, 1 1/2 tsp baking powder, 1/2 tsp baking soda, 1/2 tsp salt, 1 cup granulated sugar, and 2/3 cup brown sugar. Mixing the dry ingredients first helps distribute the leavening evenly so the cake bakes with a consistent crumb. Take a moment to break up any cocoa powder clumps. That small step helps the batter come together more smoothly once you add the wet ingredients.

5-Fifth Step: Mix the wet ingredients In another bowl, whisk together 2/3 cup vegetable oil, 3 large eggs, 3/4 cup sour cream, 2/3 cup whole milk, and 2 tsp vanilla extract. Stir until the mixture looks even and silky. Vegetable oil keeps this cake moist for longer than butter, which is one reason it works so well in bundt cakes. Pour the wet mixture into the dry ingredients and stir just until everything is combined. Stop as soon as you no longer see dry flour. Overmixing can make the cake dense instead of tender.

6-Sixth Step: Layer the batter and filling Spoon most of the chocolate batter into the prepared bundt pan, reserving a few tablespoons for the top. Use a spatula to level the batter so the cheesecake filling has a stable base. Then spoon the raspberry cheesecake filling into the center of the batter, keeping it away from the sides of the pan. That central placement helps prevent leaking and sticking. After the filling is in place, dollop the remaining batter over the top. Try not to fully cover the filling layer, because a little peek of cheesecake makes the inside look lovely when sliced.

7-Seventh Step: Bake until set Bake for 45 to 55 minutes, or until a toothpick inserted into the cake portion comes out clean. The exact time depends on your oven and the material of your pan, so start checking around the 45-minute mark. The top should look set, and the cake should spring back lightly when touched. If the top browns too quickly, loosely tent it with foil during the last part of baking. That can help the cake finish baking without darkening too much.

8-Eighth Step: Cool carefully Once the cake is done, cool it in the pan for 5 minutes. If you want, brush the top with syrup made from 1/3 cup granulated sugar and 1/4 cup water while the cake is still warm. The syrup adds a little shine and extra moisture. Let the cake rest in the pan for 1 hour. Then invert it onto a wire rack and let it cool for another 30 minutes. Cooling fully before unmolding is important, because rushing this step can cause cracks or sticking.

9-Ninth Step: Make the chocolate ganache drip To finish, heat 1/2 cup heavy cream until it just begins to simmer. Pour it over 2/3 cup chopped dark or semi-sweet chocolate and let it sit for 2 minutes. Stir until smooth and glossy, then let it cool until pourable. Spoon or drizzle the ganache over the cooled cake so it runs gently down the sides. Garnish with fresh raspberries or chocolate shavings if you want a bakery-style finish.

10-Final Step: Slice and serve Once the ganache sets, slice the cake into 12 pieces. One slice contains about 450 calories, so the portion size feels just right for a rich dessert. Serve it with coffee, tea, or a glass of cold milk for a satisfying finish.