Preheat and Prepare: Preheat your oven to 350°F (175°C). Line a 12-cup muffin tin with cupcake liners.

Combine Dry Ingredients: In a medium bowl, whisk together the flour, sugar, baking soda, salt, and cocoa powder. Set aside.

Mix Wet Ingredients: In a large bowl, whisk the oil, buttermilk, egg, food coloring, vanilla extract, and vinegar until smooth and fully combined.

Combine Batter: Add the dry ingredients to the wet ingredients and whisk gently until just combined. Be careful not to overmix; a few small lumps are okay.

Bake: Divide the batter evenly between the 12 liners, filling each about ⅔ full. Bake for 18-22 minutes, or until a toothpick inserted into the center of a cupcake comes out clean. Allow the cupcakes to cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.

Make Frosting: While the cupcakes cool, beat the softened butter and cream cheese together with an electric mixer on medium speed until smooth and creamy. Gradually add the sifted confectioners’ sugar, vanilla, and salt, beating on low until incorporated, then switch to high speed and beat for 2-3 minutes until fluffy.

Frost: Once the cupcakes are completely cool, frost them with a thick layer of cream cheese frosting using a piping bag with a round or star tip, or simply spread it on with a knife.

Decorate: Gently press two slivered almonds into the frosting on each cupcake to create fangs. Using a spoon or a small piping bag, drizzle the warmed jam from the top of the cupcake down past the fangs to create a “blood” effect.