Begin by patting the salmon dry with a paper towel and season both sides with salt and pepper.
Heat a non-stick skillet over medium-high heat and add half the olive oil. Once the oil is shimmered, place the salmon skin-side down (if applicable) and sear for about 3-4 minutes until a golden crust forms.
Flip the salmon carefully and cook for another 2-3 minutes until the salmon is cooked through but still moist in the center. Remove from the skillet and set aside.
For the cauliflower mash, steam the cauliflower florets until they are very tender, about 8-10 minutes. In the last minute of steaming, add the garlic to soften its flavor.
Transfer the steamed cauliflower and garlic to a blender or food processor. Add the unsalted butter and the remaining olive oil, then blend until smooth. Season with salt and pepper to taste.
Steam the asparagus until tender-crisp, about 4-5 minutes. Alternatively, you can lightly sauté them if preferred.
To plate, place a generous serving of cauliflower mash on the plate, arrange the steamed asparagus alongside, and top with the seared salmon fillet. Garnish with an extra sprinkle of salt and pepper if desired.