Step 1: Preheat your oven to 350°F (175°C) and grease two 8-inch round cake pans. Line the bottoms with parchment paper for easy removal.
Step 2: In a medium bowl, whisk together the flour, sugar, baking soda, salt, and cocoa powder.
Step 3: In a large bowl, beat together the oil, buttermilk, eggs, food coloring, vinegar, and vanilla until well combined. Gradually add the dry ingredients to the wet ingredients and mix until smooth.
Step 4: Divide the batter evenly between the prepared pans and bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean. Let the cakes cool completely in the pans before removing.
Step 5: For the frosting, beat the cream cheese and butter until smooth. Gradually add powdered sugar and vanilla, whipping until light and fluffy. Frost the cooled cake layers, including the top and sides.
Step 6: In a small bowl, mix the corn syrup, cornstarch, and red food coloring until it reaches the desired ‘blood’ shade. Using a spoon or squeeze bottle, carefully drip the mixture over the edges of the chilled cake.