Preheat your oven to 350°F (175°C) and line a muffin tin with cupcake liners.

In a mixing bowl, combine all-purpose flour, granulated sugar, cocoa powder, baking soda, and salt.

In another bowl, whisk together softened unsalted butter, large eggs, buttermilk, vanilla extract, and red food coloring until smooth.

Gradually mix the wet ingredients into the dry until just combined; be careful not to overmix.

Fill each cupcake liner about two-thirds full with the vibrant red velvet batter.

Place them in the preheated oven and bake for 18-20 minutes, or until a toothpick inserted into the center comes out clean.

Once baked, remove them from the oven and allow the cupcakes to cool completely on a wire rack.

After the cupcakes have cooled, use a small knife or melon baller to hollow out the center of each one.

In a separate bowl, mix red velvet cake crumbs, sweetened condensed milk, and additional red food coloring.

Generously fill each hollow with this creamy 'blood' filling.

To create the buttercream frosting, beat softened unsalted butter in a bowl until creamy and smooth.

Gradually add powdered sugar along with milk or heavy cream, mixing until the consistency is light and spreadable.

For an extra spooky touch, swirl in a few drops of ivory or peach food coloring.

Once the frosting is ready, generously frost the tops of the cooled cupcakes.

Adorn each cupcake with candy fangs or red gelatin dots.

Drizzle the cupcakes with red syrup or edible red gel to create a 'bloody' effect.