Preheat the oven to 200ºC/400ºF/gas 6.
Scrub the potatoes clean, halving any larger ones so all the potatoes are of even size, cook in a pan of boiling salted water over a medium-high heat for 10 to 12 minutes, or until cooked and starting to soften
Top and tail the green beans and add to the pan for the final 2 minutes. Pick the basil leaves.
Strain the potatoes and green beans and tip into a large bowl. Halve and add the tomatoes, then pit the olives (if desired) and add with half the basil leaves.
Add ½ a tablespoon of olive oil, toss together and tip into a roasting tray. Shake into an even layer and season with sea salt and black pepper.
Place the salmon fillets into the bowl, add ½ a tablespoon of olive oil, and squeeze in the juice of ½ a lemon. Season lightly and toss to coat. If using a whole side of salmon use a basting brush to coat the salmon in the mix.
Lay the salmon fillets (or side) on top of the vegetables, skin-side up. Slice off 4 rounds of lemon and lay on top of the salmon, then roast for 10-15 minutes (fillets), 20-25 minutes for a whole side or until cooked through.
Add the remaining Basil into a pestle and mortar with a clove of peeled garlic, and bash until a rough paste. Season with sea salt and add the yoghurt and mustard and squeeze of lemon juice, serve on top or to the side of the salmon.