1) Preheat oven to 180C/Gas 4.
2) Combine spice ingredients in a spice grinder and grind until you have a fine powder.
3) Take two large baking sheets and spread crisps out evenly. Place in the oven for about 5 to 7 minutes, until they are just warmed through and release some of their oil (this will help the spice mixture stick). Sprinkle spice mix over the warm crisps, or toss crisps and spice mixture together in a very large mixing bowl.
Grate fresh lime zest over the top and serve.