Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Peel and cube the sweet potatoes into bite-sized pieces, then chop the cauliflower and onion.
In a large bowl, toss the sweet potatoes, cauliflower, and onion with 2.5 tablespoons of olive oil, garlic powder, oregano, salt, and pepper.
Spread the seasoned vegetables in a single layer on the baking sheet and roast for 25-30 minutes until tender and golden brown.
While the vegetables roast, prepare the white rice according to package instructions until fluffy.
Pat the salmon fillet dry with a paper towel and season both sides with the remaining salt and pepper.
Heat the remaining 1.5 tablespoons of olive oil in a large skillet over medium-high heat.
Place the salmon in the pan and sear for 4-5 minutes per side until the skin is perfectly crisp and the center is cooked to your preference.
Dice the fresh tomato and stir it into the cooked rice along with the sesame seeds.
Divide the rice and roasted vegetables between plates, top with the pan-seared salmon, and finish with a sprinkle of crumbled goat cheese.