Preheat oven to 220°C (or 200°C fan bake).Bring a medium pot of salted water to the boil.
Prep white beans and toss on a lined oven tray with oil. Season with salt and bake for about 20 minutes, until golden and crispy
Place egg in a small pot and cover with water. Bring to the boil, reduce to a simmer and cook for 3 minutes. Drain and cool under cold tap before peeling. Cut egg in half, season with salt and pepper and set aside.
Cook green beans in pot of boiling water for about 3 minutes, until bright green and tender. Drain and set aside. Prep lettuce and tomatoes and toss in a medium bowl with vinegar. Set aside for serving.
Pat fish dry and remove any remaining scales or bones. Cut any larger fillets in half. Toss in a medium bowl with French seasoning and mustard, until evenly coated
Heat oil in a large fry-pan on medium-high heat. Cook fish for about 2 minutes each side, depending on thickness, until just cooked through.
Serve salad, green beans and fish topped with egg, white beans, olives, parsley and mustard mayo