Microwave beef mince and lentil hotpot

Name: Microwave beef mince and lentil hotpot
Ingredients: 600g/1lb 5oz potatoes, each about 150g/5½oz, well scrubbed (see Tip below); 1 onion, finely chopped; 2 carrots, about 200g/7oz, peeled and diced; 250g/9oz lean beef mince; 400g tin lentils (any variety), drained and rinsed; 15g/½oz plain flour; 250ml/9fl oz hot beef stock, made with 1 stock cube; 3 tbsp tomato ketchup; ½ tsp dried mixed herbs; 25g/1oz cheddar, finely grated; pinch paprika (optional); 250g/9oz frozen peas; ½ head broccoli, about 200g/7oz, cut into small florets and halved; freshly ground black pepper; chopped fresh flatleaf parsley, to garnish (optional)