Melt butter over low heat in a large pot. Add marshmallows and stir until completely melted. This will take a few minutes. Be patient, it’s worth it.
Add vanilla extract, brown sugar, salt, and cinnamon. Stir until combined.
Add Rice Krispies cereal. Stir until well coated with marshmallow deliciousness.
Add finely chopped chocolate. Stir until just combined.
Grease a 9x13 pan (I spray the pan with Pam).
PourChurro Rice Krispie mixture into the pan. Press into an even layer.
Microwave dark chocolate chips and pat of butter, until completely melted, stopping to stir frequently. Use a spoon to haphazardly drizzle chocolate over Churro Rice Krispie treats.
Put chocolate-drizzled Churro Rice Krispie Treats in the fridge for around a half-hour to set chocolate.
Remove from fridge and cut into squares. Eat.