Pat the salmon fillet dry and season with salt and pepper.
Heat a non-stick skillet over medium-high heat. Add a small drizzle of olive oil.
Sear the salmon skin-side down for about 4-5 minutes until the skin is crispy, then flip and cook for an additional 3-4 minutes or until cooked through.
Meanwhile, steam the cauliflower florets until very tender, about 8-10 minutes.
In a separate pan over medium heat, lightly sauté the garlic in a little olive oil until fragrant, then add the green beans and a splash of lemon juice, cooking for 3-4 minutes until they are crisp-tender.
Once the cauliflower is soft, transfer to a bowl and mash with a fork or immersion blender. Drizzle in the remaining olive oil, season with salt and pepper, and stir until smooth.
Plate the cauliflower mash, lay the seared salmon on top or alongside, and arrange the garlic green beans on the side. Sprinkle the Parmesan cheese over the mash for added flavor.
Finish with a squeeze of fresh lemon juice and serve immediately.