In a small pot, combine rice, 1¼ cups water (2¼ cups for 4 servings), and a pinch of salt. Bring to a boil, then cover and reduce to a low simmer. Cook until rice is tender, 15-18 minutes.

Keep covered off heat until ready to serve.

Meanwhile, wash and dry produce.

Trim and thinly slice cucumber. Trim and thinly slice scallions, separating whites from greens. Trim and discard root end from lettuce; separate leaves.

In a medium bowl, combine cucumber, scallion greens, vinegar, ¼ tsp sugar, ¼ tsp salt, and as much Sriracha as you like (½ tsp sugar and ½ tsp salt for 4 servings).

Set aside, stirring occasionally, until ready to serve.

Heat a drizzle of oil in a large, preferably nonstick, pan over medium-high heat. Add beef* and scallion whites; season with pepper. Cook, breaking up meat into pieces, until browned and cooked through, 4-6 minutes.

Remove pan from heat. (Carefully drain any excess grease from pan.)

Stir bulgogi sauce and sesame seeds into pan with beef mixture until evenly coated.

Fluff rice with a fork.

Divide lettuce leaves between plates. Fill with rice, beef bulgogi, and as many spicy pickles (draining first) as you like. Serve.