Preheat oven to 350 °F (177 °C) degrees and spray a 9 in 12 C bundt pan with Pam baking spray
Using a large bowl and hand beater, beat the cake mix, eggs, milk and butter until combined and smooth
Divide the cake batter into two bowls
Mix in about 4-7 drops of red gel food coloring into one of the cake mix bowls
Pour about ¼ of the none colored cake batter into the bundt pan
Drop dollops of the red cake batter on top of the other batter and swirl lightly with a butterknife
Pour another ¼ of the none colored batter on top of the other batter
Drop more dollops of the red cake batter on top and swirl some more
Repeat until all the batter has been combined into the bundt pan
Bake in the oven for 25-35 minutes or until a toothpick comes out clean
Allow to cool in the bundt pan for 15 minutes before flipping over onto a flat serving platter
Using a small pot, bring the 1 ½ C heavy whipping cream to a rolling simmer
Whisk in a few drops of the red gel food coloring and whisk until combined. Add in a few more drops of red to get the correct shade of red for blood
Pour the hot heavy whipping cream over the 3 C white chocolate chips and let sit for a few minutes before whisking until smooth
Allow to cool for about 10 minutes while occasionally whisking to avoid a crusting on top
Once the cake has cooled completely, pour about ¾ of the red white chocolate ganache into the center opening of the bundt cake
Carefully and slowly place the stroopwafel over the center of the bundt cake
Allow the red ganache to set for about 10 more minutes
Using a small pot, bring the 1 C of heavy whipping cream to a rolling simmer and pour over the dark chocolate chips
Allow to sit for 5 minutes before whisking until smooth
Pour the chocolate ganache over the entire cake, making sure the center is completely covered
Reheat the leftover red chocolate ganache and mix after every 15 seconds until the ganache is thin and runny
Using a fork, dip it into the red ganache and doing a flick motion with your wrist, create a splatter look all over the cake
Allow to set for 15 minutes before enjoying
Notes
Use a butter knife for swirling: To create an artistic swirling effect in your cake, use a butter knife. It provides better control, and the flat edge blends the colors without mixing them all.
Monitor the baking process: All ovens are different. Start checking the cake with a toothpick about 10 minutes before the recommended baking time to prevent over-baking.
Stroopwafel Placement: Be gentle when placing the stroopwafel. Add it only when you're sure the ganache has thickened enough to support its weight; otherwise, it might sink.
Ganache consistency: If your ganache thickens too much before you're ready to use it, gently reheat it while stirring until you achieve the desired consistency.
Cake Cooling: Always let your cake cool completely before you glaze it. Glazing a warm cake can cause the ganache to melt and slide off.
Blood Splatter: Practice your flicking technique on a piece of parchment paper before moving on to the actual cake for a realistic blood splatter effect.