Combine the lemon juice, extra-virgin olive oil and minced garlic in a mixing bowl. Marinate the shrimp in this mixture for 15-20 minutes.
Meanwhile, prepare the tabbouleh by coating the bulgur wheat in 50ml of the olive oil and pouring over the boiling water. Cover the bowl tightly with clingfilm and let it stand for 10 minutes.
Drain the bulgur wheat through a sieve, pressing on it to remove any excess water. Transfer to a large mixing bowl and toss with the pepper, tomato, red onion, cucumber. Add the rest of the olive oil, lemon juice and chopped mint and toss well again. Season to taste and chill until needed.
Heat the grill to hot and then thread the prawns onto the metal skewers, fitting 3-4 per skewer. Intersperse the prawns with chunks of the lemon.
Grill for 8-10 minutes until pink and cooked. Remove and transfer to serving plates. Serve alongside small bowls of the tabbouleh.