Preheat oven to 350F (175C) and line the bottoms of three 8” round cake pans with parchment paper and grease and flour the sides. Set aside.

In a large mixing bowl, whisk together flour, sugars, cocoa powder, baking soda, and salt.

Add oil and melted butter to flour mixture, stir until fully combined.

Add eggs and vanilla extract and stir until fully combined and batter is uniform.

Gradually add buttermilk, stirring until combined.

Slowly and carefully, add hot water or coffee, stirring until completely combined. Scrape sides and bottom of the bowl with a spatula to ensure all ingredients get incorporated.

Divide batter evenly into prepared cake pans and bake in preheated 350F (175C) oven for 24-25 minutes. When cakes are finished baking, a toothpick inserted into the center should come out completely clean or with a few moist crumbs.

Allow cakes to cool in their pans for 10-15 minutes, then run a knife along the edges to loosen from pans and carefully invert onto cooling racks. Allow to cool completely before decorating.

While cakes are cooling, prepare the raspberry filling.

In a small saucepan, combine sugar and cornstarch, whisk until combined.

Add raspberries, water, and lemon juice and stir together.

Heat saucepan on your stovetop over medium heat and cook, stirring constantly, until berries release their juices and mixture starts to bubble. This can take 5-10 minutes, do not increase your heat from medium, you want everything to heat slowly.

Continue stirring constantly and cook until thickened (this usually takes me about 2 minutes after the mixture begins bubbling). This mixture will appear to only slightly thicken, you’ll notice that when you pull your spatula through the mixture you leave a trail.

Transfer mixture to a heatproof container and allow to cool to room temperature before proceeding.

In a large mixing bowl (or the bowl of your stand mixer with a paddle attachment) use an electric mixer to beat butter on low speed until smooth and creamy.

Add about half of the powdered sugar, cocoa powder, and salt and beat on low speed until well combined.

Gradually add remaining powdered sugar, mixing on low speed, until all sugar is added.

While mixing on low speed, add ⅓ cup of the raspberry filling, a heaping spoonful (about a tablespoon) at a time, until all filling is evenly incorporated.

Gradually add heavy cream as needed and stir until icing is a smooth, pipe-able consistency. Place frosting into a piping bag with a large open tip.

Once cakes are completely cooled, level cakes if needed.

Place one cake layer on serving platter. Spread a very thin layer of frosting over the top of the cake layer. Pipe a dam of frosting around the edge of the cake.

Spread half of your remaining raspberry filling inside the piped dam. Top with the next layer of cake and repeat the process.

Top with the last layer of cake. Use the rest of the frosting to spread an even layer around the sides and top of the cake. (I like to do a crumb coating on the cake and refrigerate for 15 minutes before doing the final layer of frosting). If desired, follow my instructions (linked in the ingredients above) for adding a ganache drip.

For best results, chill cake in the refrigerator for at least 30 minutes before slicing and serving.