Heat oven to 200C/180C fan/gas 6.
Place the chips on a non-stick
baking tray, toss with oil and Cajun
seasoning, then spread out in a
single layer. Pop in the oven and
bake, turning once, for 20-25 mins
or until golden and crisp. Season.
Meanwhile, mix the mayonnaise,
chives and mustard in a small
bowl and season. Spread the mix onto 2 of the slices of bread.
Layer 1 spread slice with radishes
and avocado. Place the other slice,
spread-side up, on top and add
the salt beef and lettuce. Top
with the final slice.
Cut up and secure with cocktail
sticks if you like, then serve
alongside the fries.