Preheat oven to 350 degrees. Heat a large ovenproof skillet over high heat. Add 1 tablespoon oil, and swirl to coat pan. Add salmon, skinned side up, and sear until golden, about 3 minutes. Flip salmon, and transfer to oven. Roast 5 minutes (for medium).
Toss together fennel, pea shoots, onion, cilantro leaves, vinegar, and remaining 3 tablespoons oil; season with salt.
Slice tomatoes, and arrange on 4 plates. Season with salt, and top with salmon. To serve, top with salad, and drizzle with oil. Season with salt, and garnish with cilantro sprigs.