Preheat the oven to 425°F. Place the cherry tomatoes on a baking sheet and drizzle with 2 tablespoons of the olive oil. Season well with salt and roast until charred and bursting, about 15 minutes.
In a large, deep skillet, heat the remaining 3 tablespoons olive oil over medium heat. Add the onion and bell pepper and season with salt and pepper to taste. Cook until the onion is translucent, about 5 minutes. Add the garlic, harissa, sweet paprika, turmeric, and smoked paprika and cook for 1 minute. Add the white wine and use your spoon to scrape up the browned bits from the bottom of the pan. Let the mixture simmer for 2 more minutes. Add the chopped tomatoes, season with salt and pepper, and cover. Cook, stirring occasionally, until the tomatoes begin to break down and start to resemble a sauce, 10 to 15 minutes. Remove the lid and cook until slightly reduced, another 10 minutes.
Check the sauce for seasoning and increase the heat to a simmer. Let it reduce until it’s thickened slightly, about 5 minutes, which will make it more flavorful and help it cling to the fish. Place the halibut in the pan, making sure to spoon sauce over the fish. Cover and simmer until the fish is no longer translucent in the middle and the flesh is flaky, 6 to 8 minutes.
Serve right in the pan with the garlicky tahini drizzled over it and topped with the roasted cherry tomatoes, fresh herbs, and additional olive oil
Garlicky Tahini
In a medium bowl, whisk together the tahini, lemon juice, garlic, salt, and ice water. It will reach a weird, lumpy consistency, but don’t be afraid. Keep whisking until it smooths out and becomes light in color (if it doesn’t, it needs more ice water, so just add a bit more). Tahini sauce with the perfect consistency will drip through the tines of a fork, but just barely. Taste for seasoning, adding more lemon juice or salt if desired. Store in a jar in the fridge for up to 1 week. If the tahini gets too thick while in the fridge, just loosen it up with a little water before using.
