Thaw salmon overnight in the refrigerator if it’s frozen.
At least 30 minutes before you plan to cook, take salmon out of the refrigerator and place on small roasting pan that you’ve sprayed with nonstick spray or olive oil, and let the fish come to room temperature.
Season with fish rub if you’re using it.
Preheat oven or toaster oven to 425F/220C.
Finely chop the pecans with a chef’s knife.
Mix together the Dijon mustard and mayo in a small bowl and use a rubber scraper to spread it over the surface of the salmon, until it’s completely covered.
Then sprinkle the pecans over the fish, pressing them down so they stick. (I put each piece of fish on the cutting board while I sprinkled it with pecans and then put them back on the roasting pan when they were covered.)
Roast the salmon for 10-12 minutes, or until it feels barely firm to the touch when it’s pressed with your finger.
Don’t overcook; the fish will continue to cook for a few minutes when you take it out of the oven.
Serve hot.
