Five Spice Chicken Kebab

Name: Five Spice Chicken Kebab
Ingredients: 500g chicken thigh, trimmed and slice to about 1 inch pieces; 1 1/2 tbsp five spice powder; 1 tbsp brown sugar plus 1 tsp brown sugar; 1 tsp garlic powder or 2 cloves garlic, finely minced; 1/2 tsp salt; 1 1/2 tbsp soy sauce; 1 tsp vinegar; 1 tsp sesame oil; 1/4 tsp cayenne pepper (put less if you don't like chilli); 2 tbsp fresh coriander, chopped; 1 1/2 tbsp vegetable oil or olive oil plus some to grease grilling pan; a handful of cherry tomatoes, rince and drained; 1 brown onion, quartered then half (triangle shape); 1 Zucchini, halves lenghtwise and slice 1cm thick; a handful of cup mushroom, damp wipe the mushroom and cut to half