- To make vinaigrette, dissolve the salt in the vinegar and add the oil, parsley, spring onions and tomato.
- Add some black pepper and whisk thoroughly.
- Let stand for 30 minutes.
- Boil the peas for 5–7 minutes and drain.
- Season the mackerel fillets with salt and pepper and sauté.
- Place the egg slices on each of four plates and top with a mackerel fillet.
- Drop the peas into the vinaigrette, mix well and divide between the portions.
- Garnish with some parsley and endive lettuce and serve.