Prepare the salmon by placing it in the freezer for about 15 minutes, then slice into ¼-inch thick planks and dice into ¼-inch cubes.

Combine diced salmon with olive oil, chopped red onion, capers, Dijon mustard, lemon zest and juice, jalapeño, and chives in a mixing bowl.

Toss all ingredients gently, let sit for 5 to 10 minutes at room temperature for flavors to meld.

Serve the tartare using a round mold for presentation or in a serving bowl alongside crackers, cucumber slices, or fresh greens.