Wash and dry produce.

Trim and thinly slice scallions, separating whites from greens. Peel and grate garlic. Trim and thinly slice cucumber.

Heat a drizzle of oil in a large pan over medium-high heat. Add pork*, scallion whites, garlic, salt, and pepper. Cook, breaking up meat into pieces, until pork is browned and scallion whites are softened, 2-4 minutes.

Add umami ginger sauce, ketchup, Sriracha, and half the sesame seeds. Cook, stirring, until sauce is thickened and pork is cooked through, 1-2 minutes more. Taste and season with salt and pepper if needed. Remove from heat and cover to keep warm.

In a medium bowl, combine cucumber, scallion greens, vinegar, remaining sesame seeds, ¼ tsp sugar (½ tsp for 4 servings), and a pinch of salt.

Halve and toast buns.

Fill buns with pork mixture and as much cucumber salad (draining first) as you like. Divide sloppy joes between plates and serve with any remaining cucumber salad on the side.