Season the salmon fillet evenly with sea salt and black pepper.
Heat a non-stick skillet over medium-high heat and sear the salmon for 4-5 minutes per side until the edges are crisp and the center is cooked through.
In a small mixing bowl, whisk together the rice vinegar, tamari, and freshly grated ginger to create the dressing.
Place the warm cooked sushi rice in a bowl and toss with half of the prepared dressing.
Thinly slice the radishes and avocado into bite-sized pieces.
Assemble the bowl by placing the seasoned rice at the base, then topping it with the seared salmon, cucumber slices, radishes, and avocado.
Tear the nori sheet into small strips and sprinkle over the top.
Drizzle the remaining dressing over the entire bowl and serve immediately.