Preheat the oven to 425 F. Line a rimmed baking sheet with foil or parchment, and spray with nonstick cooking spray.
Roast the broccoli rabe and the salmon: Place the broccoli rabe on the prepared baking sheet and drizzle over 1 tablespoon oil, ½ teaspoon of the salt, then add the garlic and red pepper flakes. Toss to coat well, then spread out on a baking sheet. Place in the oven, and cook for 10 minutes. Remove the baking sheet from the oven, shove the broccoli rabe over to the side of the baking sheet to make enough room for the 4 salmon filets. Place the salmon filets skin side down on the baking sheet and drizzle about 1 teaspoon of olive oil over each piece and rub to coat the top and sides. Season with salt and pepper. Roast everything for 8 to 10 minutes more, until the broccoli rabe is tender and the salmon flakes easily. The internal temperature of the salmon should be at least 145 F in the thickest part.
While the salmon and broccoli rabe are roasting, make the Herbed Mayonnaise: Place the parsley, basil, cilantro, dill and oregano in the food processor and pulse to chop. Add the mayonnaise and pulse several times to blend. Pulse in the lemon juice, salt and several grinds of pepper. With the motor running, very slowly drizzle in the olive oil through the feed tube on top or with a slow and steady hand until the mixture is completely incorporated and — if things went well — somewhat fluffy. Scrape down the sides and blend again. Taste and adjust the seasoning as needed.
Slide a thin spatula under each piece of fish, separating it from the skin and place each piece on a plate. Distribute the broccoli rabe amongst the 4 plates next to the fish. Spoon the Herbed Mayonnaise over the salmon, or pass it on the side as desired. Sprinkle the top of the fish with slivered fresh basil if desired.
Notes
If spicy isn’t your family’s thing, you can leave out the red pepper flakes in the broccoli rabe side.
You can also use small spears of regular broccoli instead of the broccoli rabe.
Or try asparagus, which will take about the same time to cook as the broccoli rabe if thick, or only the amount of time it takes for the salmon to roast if the stalks are skinny.
Skip the cilantro if you have cilantro-haters in your house; it’s a great herb to use, but it’s not for everyone.