Pat the salmon dry and finely dice into small, even cubes; place in a small bowl.
Add 1 teaspoon of the olive oil to the salmon, season with sea salt and freshly cracked black pepper, then gently toss to combine.
Cut the tomato in half and scoop out the seeds and juices with a spoon; discard the seeds and juices, then finely dice the tomato.
In a separate bowl, combine the diced tomato, chopped chives and the remaining 1 teaspoon olive oil; season with salt and pepper and gently mix.
Arrange the seasoned salmon on a serving dish, spoon the tomato and chive mixture on top, and serve immediately.