Thai Chicken Vermicelli Bowl

• 500 g chicken mince
• 1 brown onion, diced
• 200 g vermicelli noodles
• 1 cucumber, sliced into batons
• 1 red capsicum, thinly sliced
• 1 carrot, grated
• 0.5 cup fresh mint leaves
• 4 tbsp crushed peanuts or cashews
• 3 tbsp fish sauce
• 3 tbsp lime juice
• 2 tbsp sweet chilli sauce
• 1 tsp sugar
• 2 tbsp chilli oil (optional)