Wash and dry produce.

Halve, peel, and finely dice onion. Core, deseed, and finely dice green pepper. Zest and quarter lime. Trim and discard root end from lettuce; separate leaves. Gently crush tortilla chips in their bag into small pieces.

Heat a drizzle of oil in a large pan over medium-high heat. Add onion, green pepper, and pork*. Season generously with salt (we used ¼ tsp; ½ tsp for 4 servings) and pepper. Cook, breaking up meat into pieces, until pork is lightly browned and onion is slightly softened, 4-5 minutes.

Add Fajita Spice Blend; cook, stirring, 30 seconds. Stir in stock concentrate, ½ tsp sugar, and 1 TBSP water (use 1 tsp sugar and 2 TBSP water for 4). Cook, stirring occasionally, until pork is cooked through, 2-3 minutes more.

Pat chicken* dry with paper towels. Cook through this step as instructed, swapping in chicken (no need to break up into pieces!) for pork.

Meanwhile, in a small bowl, combine sour cream, lime zest, and juice from one lime wedge. Add water 1 tsp at a time until mixture reaches a drizzling consistency. Season with salt and pepper.

Remove pan with pork filling from heat; sprinkle with Mexican cheese blend. Cover pan until cheese melts, 1-2 minutes.

Divide lettuce leaves between plates; fill with pork filling. Drizzle with lime crema and sprinkle with crushed tortilla chips. Serve with any remaining lime wedges on the side.