Rinse the jasmine rice until the water runs clear, then cook according to package instructions.

While rice cooks, combine the shredded carrot and sliced cucumber in a small bowl with the rice vinegar and a pinch of salt. Toss to coat and set aside to quick-pickle.

In a large mixing bowl, combine the ground beef, lemongrass paste, minced garlic, fish sauce, brown sugar, and panko breadcrumbs. Mix gently with your hands until combined, then roll into 12-16 small meatballs.

Heat a large skillet over medium-high heat with a splash of oil. Add the meatballs and cook for 8-10 minutes, turning occasionally, until browned on all sides and cooked through.

In a small bowl, whisk together the mayonnaise and Sriracha sauce to create the spicy drizzle.

To assemble, divide the cooked rice among four bowls. Top with the warm meatballs, a generous portion of the pickled carrots and cucumbers, and fresh cilantro.

Finish by drizzling the Sriracha mayo over the top of each bowl before serving.