Remove salmon from the refrigerator 20 minutes before cooking. Pat the skin completely dry with paper towels and season both sides generously with salt and pepper.

Bring a medium saucepan of salted water to the boil. Add the frozen peas and cook for 3-4 minutes until tender. Drain and set aside.

In the same pan, heat 1 tablespoon olive oil over medium heat. Sauté the shallot for 2 minutes until softened, then add garlic and cook for 30 seconds until fragrant.

Add the cooked peas, vegetable stock, and mint leaves to the pan. Simmer for 2 minutes, then transfer to a blender and purée until smooth. Season with salt, pepper, and lemon juice. Keep warm.

Heat remaining olive oil in a large non-stick frying pan over medium-high heat until shimmering. Place salmon fillets skin-side down and press gently with a spatula for 30 seconds to ensure even contact.

Cook salmon skin-side down for 4-5 minutes until the skin is deeply golden and crispy. Flip and cook for a further 2-3 minutes until the internal temperature reaches 63°C for medium or 74°C for well-done.

Spoon the warm minty pea purée onto plates, place the crispy salmon on top skin-side up, and garnish with lemon zest, fresh mint leaves, and chives. Serve immediately.