Cut a 3in section of cucumber unpeeled into 1/4 inch dice and set aside. Peel and seed remaining cucumber, cut into chunks and place into a food processor. Pulse the cucumber until they are liquified but still retain some chunkiness (May need to be done in batches). Remove to a large bowl and add 4 tablespoons of olive oil, the vinegar, jalapeño and salt and pepper. Set gazpacho aside.
In a 12 to 14 inch sauté pan add the remaining 3 tablespoons of olive oil over high heat until just smoking. Score each fish fillet on the skin side, season aggressively with salt and pepper on both sides and place them in the pan skin side down, working in batches if necessary. Cook, undisturbed until the skin is crispy and moves from the bottom of the pan without tearing, about 5 minutes. Carefully turn the fillets and cook on the flesh side about 1-2 minutes. Add the tomatoes to the hot pan and toss gently until they are heated through and just about to burst.
Serving: Divide the gazpacho evenly among the 4 bowls. Place a fillet on top of each puddle of gazpacho. Scatter a few tomatoes, diced cucumbers around and over each fillet. Sprinkle with red pepper flakes and serve immediately.