Rinse salmon and pat dry with a kitchen towel. Heat a skillet to medium-high and melt butter with 2 tablespoons of olive oil. Sear salmon skin side up for 3 to 4 minutes. Flip and sear 2 more minutes.
In a medium bowl, zest rind of one orange and squeeze out all the juice. Whisk in half the lemon juice, honey, vinegar, and ground mustard seed. Move salmon to the sides of the pan and pour the orange juice mixture around the salmon. Bring to a simmer until reduced to a nice syrup.
When salmon is almost finished, start preparing the zucchini noodles. In a large skillet, heat 1 tablespoon olive oil over medium heat. Add zucchini noodles, garlic, salt, crushed red pepper, and black pepper, sautéing for 3 minutes. Add a few tablespoons water and heat another minute or so. Noodles should have the firmness of al dente pasta. Mix in parsley and the remaining half of the lemon juice.
When salmon is cooked to your liking, plate the zucchini noodles and top with salmon. Evenly pour sauce over the salmon and noodles. Cut second orange into thin slices, for garnish. Serve hot.
If your zucchini noodles or salmon are thinner or thicker than recommended, adjust cook time accordingly.
Per serving: 387 calories, 21 grams fat (5 grams saturated fat), 28 grams total carbohydrates, 2.5 grams fiber, 25 grams protein
