Wash and dry all produce. Halve, peel, and finely dice onion. Core and seed poblano, then cut into 1/3-inch squares. Core and seed tomatoes, then cut into 1/3-inch cubes. Roughly chop cilantro. Cut lime into wedges. Drain pineapple, reserving juice; roughly chop fruit.

Combine 2 TBSP onion, 1/4 cup poblano, tomatoes, half the cilantro, pineapple, and a squeeze of lime in a medium bowl. In a separate small bowl, combine sour cream with a squeeze of lime. Season with salt, pepper, and more lime to taste.

Heat a large drizzle of oil in a large pan over medium-high heat. Add remaining onion and poblano. Season with salt, pepper, and half the taco spice. Cook, tossing, until softened, about 2 minutes.

Add beef to pan, breaking up meat into pieces. Season with salt, pepper, and remaining taco spice. Cook, tossing occasionally, until browned and cooked through, 2-3 minutes. (TIP: Carefully pour out any excess grease in pan if mixture seems oily.) Stir in reserved pineapple juice and remove pan from heat.

While beef cooks, wrap tortillas in a damp paper towel and microwave on high until warm, about 30 seconds.

Divide beef mixture between tortillas. Spoon over salsa and crema. Sprinkle with remaining cilantro. Serve with any remaining lime wedges on the side for squeezing over.