Chilli beef with jacket potatoes

Name: Chilli beef with jacket potatoes
Ingredients: 3 baking potatoes, washed and dried; 4 tsp rapeseed oil; 1½ tsp ground cumin; 1½ tsp ground coriander; ½ tsp ground cinnamon; 1½ tsp mild chilli powder; 300g/10½oz sirloin or rump steak, fat removed, cut into 1cm/½in-thick strips; 1 red onion, thinly sliced; 1 red pepper, seeds removed, thinly sliced; 2 garlic cloves, finely chopped; ½–1 red chilli, seeds removed, sliced; 400g tin chopped tomatoes; 1 tbsp roughly chopped coriander leaves; sea salt and freshly ground black pepper; 100g/3½oz sour cream; 45g/1½oz mature Cheddar. grated; 30g/1oz jalapenos, sliced