Combine milk and sugar in a large pot over medium heat until milk begins to simmer.
Simmer for 4 minutes, stirring to combine, until sugar is dissolved.
Add the chocolate chips and red food coloring. Stir until combined and chocolate is melted.
Remove from heat and stir in the vanilla and red velvet syrup.
Pour Bloody Hot Chocolate into two mugs, a garnish with whipped cream, and sprinkles if using.
If adding a spiced rum shot, use a plastic shot syringe and draw 1-oz of rum per syringe, and some of the chocolate mixture. Shake gently to combine and place in the mug as shown. If you don't want to use rum, but want to use the syringe as a decoration, then just draw up some of the hot chocolate into the syringe and place it as shown.