Adapted from Whole Bowls by Allison Day. I love Allison's shortcut harissa recipe using tomato paste and dried chilis. I also added coriander seed to the mix and toast all the spices before grinding them.
Harissa will keep, refrigerated, for two weeks, or frozen, for up to 2 months.
When I don't want to dirty my food processor, I make the harissa in my mortar and pestle. It requires a little more effort, but works just as well.