Pat the salmon fillet dry and season both sides with salt and pepper.
Heat half of the olive oil in a skillet over medium-high heat. Once hot, add the salmon, skin side down if applicable, and sear for about 4-5 minutes. Flip and cook for an additional 3-4 minutes until the fish is cooked through but still moist.
While the salmon cooks, bring a small pot of water to a boil and blanch the green beans for 2-3 minutes until they are vibrant and tender-crisp. Drain and set aside.
In a separate pot, steam the cauliflower florets until very tender, about 8-10 minutes.
In a blender or using a fork, mash the steamed cauliflower. Stir in a small drizzle of olive oil, a minced garlic clove, salt, and pepper to create a creamy mash. Adjust seasoning to taste.
In a small pan, heat the remaining olive oil over medium heat. Sauté the chopped garlic for about 1 minute until fragrant, then add the blanched green beans and toss briefly to coat with the garlic flavor. Season with a pinch of salt.
Plate the cauliflower mash as a base, position the seared salmon on top or to the side, and serve the garlic green beans alongside. Garnish with additional pepper if desired.