Wash and dry produce.

Halve, peel, and thinly slice shallot. Trim and discard root end from lettuce; separate leaves. Reserve 6 whole lettuce leaves (12 leaves for 4 servings); finely chop remaining lettuce. Halve tomato lengthwise and thinly slice crosswise into half-moons.

In a small microwave-safe bowl, combine shallot, vinegar, ½ tsp sugar, and ¼ tsp salt (1 tsp sugar and ½ tsp salt for 4 servings). Microwave until shallot turns pink, 30-60 seconds.

Set aside to pickle, stirring occasionally.

Heat a drizzle of oil in a large, preferably nonstick, pan over medium-high heat. Add beef*, stock concentrate, 2 tsp Shawarma Spice Blend (4 tsp for 4 servings) (be sure to measure—we sent more!), half the garlic powder (you’ll use the rest later), a pinch of salt, and pepper.

Cook, breaking up meat into pieces, until cooked through, 4-6 minutes. Carefully drain any excess grease from pan.

While beef cooks, in a second small bowl, whisk together yogurt, mayonnaise, and remaining garlic powder. Taste and season with salt and pepper.

Fill lettuce leaves with shredded lettuce, beef, tomato, and pickled shallot (draining first).

Divide lettuce wraps between plates and drizzle with as much white sauce as you like. Serve.