If you can't get hold of rice noodles, try making the salad with cooked, cooled white rice instead.
Mix together the lemongrass paste, ginger, chilli, oil and 1 tbsp of the fish sauce. Smear the mixture all over the pork chops, then set aside to marinate while you make the salad.
Tip the noodles into a large bowl. Pour over a kettleful of boiling water, then leave to sit for 5 mins until the noodles are soft (or prepare them according to pack instructions). Drain the noodles into a sieve. Run under the cold tap until cool, then drain again and tip back into the bowl. Whisk the remaining 2 tbsp fish sauce with the lime zest and juice and sugar. Pour over the cold noodles. Slice the cucumber into thin strips, then toss through the salad along with the mint leaves.
Heat a griddle pan until smoking hot. Griddle the chops for 5 mins on each side or until cooked through, then serve alongside the noodle salad.