The purpose of gremolata is to brighten and enhance whatever you put it on. I make my gremolata pretty chunky. I like being able to really see and taste the different ingredients that are in it. And with the silky texture of the baked salmon, it's a perfect complement in terms of texture.
I promise you that once you make this, you'll be looking for lots more things to put this on and for lots more ways you can use horseradish root in your cooking.
*Note: Make sure to peel the root first.
Combine all of the ingredients in a small bowl and mix thoroughly. Set aside.
Preheat the oven to 325 degrees.
Lightly oil a baking dish with olive oil. Place the fillets skin side up in the center of the dish. Make sure that there is some room between them.
Bake until the internal temperature of the fish reaches 125 degrees, about 15 minutes. Remove from the oven and transfer to plates. Top with the gremolata and serve.