Rub the skin of the salmon with olive oil and arrange the portions skin side down on a parchment paper-lined baking sheet.
Season each portion of salmon generously with salt and pepper and 1/2 teaspoon brown sugar. Let stand for 10 minutes or until the brown sugar starts to liquify.
Roast the salmon at 425 degrees F for 10-12 minutes or until the center of the fish is cooked through and just starts to flake. Let stand until ready to serve.
Cut the zucchini with a spiralizer using the thick spiraling blade. Set aside.
Sauté the onion in 1 teaspoon olive oil and the butter in a large sauté pan over medium-high heat until softened and translucent. Add the garlic and sauté for 1 minute. Add the tomatoes with their juices and the wine. Cook for 5-8 minutes or until the liquid is reduced by a 1/4.
Reduce the heat to medium and stir in the corn, cream, tarragon, 1 1/2 teaspoons salt and 1/4 teaspoon pepper.
Bring the sauce to a simmer. Reduce the heat to low.
Add the zucchini and cook until it is softened but still holds the spiral shape, tossing in the sauce constantly. Season with more salt and pepper to taste.
Serve immediately with the salmon. Spoon extra sauce over the top and garnish with more tarragon if desired.