Preheat Anova sous vide machine to 150 F (65.5 C), and while it's preheating mix together all of the pork patty ingredients and form the mixture into 8 small patties - seal them in a bag, put in water bath and set timer to 2 hours.
Make the noodle dressing in a pestle and mortar by pounding the palm sugar and chilli, then add the lime juice and fish sauce – NB: if you’re using brown sugar you can simply combine the ingredients in a bowl. Toss the noodles in the dressing to combine.
When the pork is finished cooking sous vide, drain the liquid from the bag, pat dry, and fry in hot oil for 1-2 minutes until you get some good colour on the outside. Arrange the lettuce leaves on a plate, put some noodles on each leaf, then the patties on top of that. Serve alongside lemon wedge and sweet chilli sauce.
