Preheat the oven to 425°F and line a baking sheet with parchment paper.
Prepare the cauliflower by ricing it in a food processor. Lightly steam the riced cauliflower until tender, about 5 minutes, then transfer to a bowl. Add a teaspoon of olive oil, a pinch of salt, and pepper, then mash until smooth. Set aside.
Arrange the asparagus on half of the baking sheet, drizzle with a little olive oil, and season with salt and pepper.
Place the asparagus in the preheated oven and roast for 10-12 minutes until tender and slightly crispy.
While the asparagus roasts, pat the salmon fillet dry with a paper towel. Season both sides with salt and pepper.
Heat a non-stick skillet over medium-high heat. Once hot, add the salmon fillet, skin-side down (if applicable), and sear for about 3-4 minutes until a golden crust forms.
Flip the salmon and cook for an additional 3-4 minutes until the fish is opaque and flakes easily with a fork.
Plate the seared salmon alongside the roasted asparagus and a serving of cauliflower mash. Serve immediately and enjoy your balanced, flavorful dinner.