Sweet potato traybake fajitas

Name: Sweet potato traybake fajitas
Ingredients: 2 tsp chilli powder; ½ tsp ground cumin; ½ tsp sweet smoked paprika; ½ tsp dried oregano; ½ tsp sea salt; 1 tbsp vegetable oil; 1 lime, juice only; 2 sweet potatoes (about 350g/12oz), scrubbed and cut into bite-sized pieces; 1 red pepper, seeds removed and cut into bite-sized pieces; 1 yellow pepper, seeds removed and cut into bite-sized pieces; 1 onion, cut into bite-sized pieces; ½ onion, finely chopped; 1 jalapeño pepper, seeds removed and finely chopped; 2 large red tomatoes, finely chopped; 1 tbsp finely chopped fresh coriander leaves; sea salt; 4 small soft tortilla wraps; 2 tbsp soured cream or coconut yoghurt; 2 tbsp guacamole (optional)