Bo Luc Lac -Shaking Beef- is a spectacularly fresh and flavourful Viêtnamese salad of mixed greens, cucumbers, pickled red onions, juicy mango, tender rice vermicelli noodles, bright herbs, and an irresistible black pepper lime dressing.
Add the beef, garlic, sugar, soy sauce, fish sauce, and sesame oil to a zipper top bag. Squish together thoroughly and refrigerate for at least one hour but up to overnight.
Drizzle half of the vegetable oil into a stainless steel or cast-iron skillet set over high heat. Add half of the beef cubes to the pan, shaking just to distribute the beef in an even layer, then leaving it to sear for 2 minutes.
Shake the pan or use a turner to stir the beef vigorously for 1-2 more minutes, or until the beef cubes are medium rare.
Combine the lime juice, olive oil, sugar, kosher salt, and black pepper in a jar with a tight fitting lid. Shake well to combine. You can store this in the refrigerator for up to two weeks.
Toss together the mixed spring greens, mint leaves, and cilantro leaves and arrange over a large serving platter.
Pile the drained, rinsed noodles in the center of the greens.
Arrange the cucumber slices, mango pieces, and pickled red onions over the greens, and arrange the lime wedges around the outside of the greens. Be sure to leave a space over the noodles as this is where you'll put the hot beef.
Drizzle about 1 tablespoon of the Black Pepper Lime Vinaigrette over everything.
As soon as the Shaking Beef is medium rare, transfer it directly from the pan to the bed of rice noodles and drizzle with about another tablespoon of the Black Pepper Lime Vinaigrette.
Divide the salad at the table, including a lime wedge with each serving. Squeeze the lime wedge over the Bo Luc Lac before eating. Serve any extra Black Pepper Lime Vinaigrette at the table to use to taste.