ROAST: Preheat the oven to 400 F / 205 C. Line a rimmed baking sheet with parchment paper and place the salmon, skin side down, onto the sheet. Brush the salmon with the tahini, then sprinkle over the everything bagel seasoning, lightly pressing the seeds into the salmon and coating it evenly. Slide the baking sheet into the oven and cook until the salmon is opaque on the outside, just beginning to flake and still just a tad pink in the middle, about 8 – 14 minutes, depending on the thickness of the fish. Remove from the oven and let cool on the tray just enough to handle.

BLANCH: Put the peas into a heatproof bowl with plenty of room and cover them with just-boiled water. Let the peas sit for two minutes, then drain away the hot water through a colander. Pop the colander under cold running water until the peas have stopped cooking and are no longer warm. Drain once again and transfer them back to the bowl.

DRESS: To the bowl with the peas, add the sliced radishes, green onions, extra virgin olive oil and lemon juice. Season with salt and pepper, to taste.

MIX: Measure all of the caper sour cream ingredients into a wide mouthed mason jar. Use an immersion blender to whip the sour cream together until it is evenly flecked with capers and herbs, but not so blended it begins to tint green. Set aside for later.

ASSEMBLE: Dividing between plates or on one large platter, pile the torn romaine lettuce and top it with the dressed spring pea salad. Flake the warm salmon and serve it alongside the simple salad and the caper sour cream immediately.