- Preheat the oven to 200°C.
- Prick the potatoes with a fork, and bake in the oven for around 45-60 minutes until the inside is soft when tested with a fork and the skin crispy.
- While the potatoes are cooking, break the mackerel fillets into chunks. Mix the mackerel and sauce with the kidney beans.
- When the potatoes are cooked, transfer to a serving plate. Make a cut in the top of the potato and open each one up. Pile on the mackerel and beans, then serve with the guacamole, sour cream and mixed leaves.
To speed up the process, cook the potatoes in a microwave oven for around 5 minutes, then finish in the oven for 25-30 minutes.