When I made that big batch of harissa a couple of weeks ago, I gave some of it away but kept a small jar for myself, even though I wasn’t sure what I would do with it. We had already planned to make grilled shrimp tacos that week (back when we were still having an unseasonable spell of beautiful weather and could reasonably eat outside), and Jon had the brilliant idea of bathing them in harissa instead of our usual lemon-garlic butter after taking them off the grill. The primary flavors in the harissa are chile pepper, cumin and caraway, so it works perfectly in a Mexican food context.
We built the tacos on flour tortillas with the grilled spicy shrimp, guacamole, sour cream, and lots of nopalitos (pickled cactus strips). It was delicious and I probably ate too much sour cream.