Pineapple Poblano Beef Tacos with Lime Crema, Cilantro, and Warm Spices

Wash and dry all produce. Halve, peel, and finely dice onion. Core and seed poblanos, then cut into ⅓-inch squares. Dice tomatoes. Roughly chop cilantro. Halve one lime; cut other into wedges for serving. Drain pineapple, reserving juice; roughly chop fruit.