1. Blanch the Canadian geoduck in boiling water for 5 – 10 seconds and then drench in an ice bath. Over a bowl, process and clean the geoduck by removing the shell, skin, and gut ball. Slice geoduck siphon into small pieces (approximately ½ inch thick). Marinate the geoduck in buttermilk overnight.
2. For the slaw: season the carrot and daikon with small amount of salt and let sit aside, in a small saucepan combine the water, mirin, and vinegar. Bring to a boil and then transfer to a bowl to let cool. Pour over the salted carrot and daikon. Set aside to let marinate overnight in the fridge.
3. The following day, fill a large pot one third of the way full with vegetable oil and heat to 350°F degrees. Batter the marinated geoduck in flour and carefully drop the battered geoduck to the oil for 2-3 minutes. The fried geoduck will turn golden brown. Add the freshly chopped jalapeno peppers and garlic oil.
4. Slice your baguettes in half and toast in the oven until crispy. 5. Building your banh mi sandwiches by adding the spicy mayo, pickled carrots, pickled daikon, cucumber, cilantro, scallion, and the fried geoduck. Finish by lightly drizzling the Nước Chấm on top for an extra kick. Enjoy!