In a bowl, combine ground lamb, grated onion, minced garlic, half of the chopped mint, cumin, coriander, salt, and black pepper. Mix well.

Divide the lamb mixture into 8 equal portions and shape them onto skewers.

Preheat a grill or grill pan to medium-high heat. Cook the lamb skewers for 3-4 minutes per side, until browned and cooked through.

Meanwhile, prepare the vermicelli noodles according to package instructions. Drain and set aside.

For the dipping sauce, whisk together lime juice, fish sauce, sugar, and the remaining chopped mint.

Arrange the cooked vermicelli noodles on a serving platter.

Place the grilled lamb skewers alongside the noodles.

Serve immediately with the mint dipping sauce on the side.