Preheat oven to 425 degrees.
Place the halibut fillets in a tin pie dish (they just fit the best this way) or, if you don't have a pie dish, place on a parchment paper lined sheet tray. Sprinkle the fish generously with salt and drizzle on 1 tbsp of olive oil.
Cover the fish with the sliced cherry tomatoes, olives and minced garlic. Sprinkle lemon juice over all then drizzle on the remaining 1 tbsp olive oil. Sprinkle one more time with sea salt.
Roast fish for 12-15 minutes until opaque. Add torn fresh basil immediately when it comes out of the oven, another squeeze of lemon and maybe a sprinkle of flaky salt. Serve.