There are many things that passionate home cooks implore others to try homemade. Believe me, you'll never turn back to the packaged, store-bought stuff again. If you haven't tried it, you have no idea what real pimento cheese is.
This is the recipe that changed it all...
Homemade Pimento Cheese
Shred all the cheese. If you buy the already shredded stuff, it won't meld into the spread properly. Chop the pimentos roughly. Mix the cheese, pimentos and sour cream. If the mixture is still dry, add more sour cream and mayonnaise a tablespoon at a time until you can easily mix it with a large spoon. You don't want it to be a gloppy consistency. When it's mixed together, place in the refrigerator for at least one hour to set. If you're going to make sandwiches, let the spread sit out for a good half hour at room temperature so it will be softer and more spreadable.
This also works if you pulse the ingredients in a food processor, but be careful not to over-mix.