Preheat your oven to 425°F.
Toss the asparagus with 1 teaspoon olive oil, a pinch of salt, and pepper. Spread them out on a baking sheet and roast for 10-12 minutes until tender and slightly crispy.
Meanwhile, steam the cauliflower until very tender, about 8-10 minutes.
In a small saucepan or microwave, gently warm the steamed cauliflower with 1 teaspoon olive oil, 1/2 teaspoon butter, and the minced garlic. Blend or mash until smooth and season with salt and pepper. Stir in 1 tablespoon of lemon juice.
Pat the 7-ounce salmon fillet dry with a paper towel and season with salt and pepper on both sides.
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 another 3-4 minutes, or until it reaches your preferred level of doneness.
To plate, spread a serving of cauliflower mash on the plate, lay the seared salmon fillet on top or alongside, and arrange the roasted asparagus around.
Finish with an extra drizzle of lemon juice over the salmon if desired.