In a small bowl, combine the freshly grated ginger, rice vinegar, water, sugar, and salt. Whisk together until well blended and set aside.
Heat a non-stick skillet over medium heat. Add the unsalted butter, allowing it to melt and become slightly bubbly. Pat the salmon filet dry and season both sides with salt, pepper, and garlic powder.
Carefully place the seasoned salmon filet into the hot skillet, skin side down. Cook for about 4-5 minutes, then flip the salmon and pour the ginger sauce over it. Cook for an additional 3-4 minutes, or until the salmon flakes easily.
Prepare your brown jasmine rice according to package instructions. Once cooked, fluff the rice and divide it among serving bowls.
To each bowl of rice, add a piece of the cooked salmon, drizzle with remaining ginger sauce, and top with green onions, avocado, and radishes. Sprinkle with furikake seasoning, soy sauce, and sesame oil.
Serve warm and enjoy!