Start out by mixing together the mayo, diced pimientos, worcestershire sauce, grated onion and a dash of cayenne.
Now for the difficult part (it's really not that bad and I think you could make it even easier by using a food processor to grate the cheese). Grate 8 oz. of sharp cheddar and 8 oz. of extra sharp cheddar. I don't know how to discuss the gauge of cheese grating options, but my Ikea cheese grater has two options, one with regular size holes and one with smaller holes, you do one block of cheese on the regular holes and one on the smaller holes. And yes, grating the cheese on the smaller holes takes longer and gets tedious, consider yourselves warned.
Stir the cheese into the mayo mixture and enjoy, it will keep in the fridge for about a week.
1 1/2 cup mayo
4 oz. diced pimientos
1 tsp. worcestershire sauce
1 tsp. finely grated onion
8 oz. sharp cheddar, grated
8 oz. extra sharp cheddar, finely grated
Mix the mayo, pimientos, worcestershire sauce, onion and cayenne together until well mixed. Stir in the cheese. Store in a covered container up to one week.