Preheat the oven to 400 degrees F. Line a baking sheet with foil or parchment paper.
If you want to pre-portion the salmon, cut the salmon into 4 equal pieces. Otherwise, place the whole salmon fillet on the prepared baking sheet skin side down.
In a small bowl, stir together the mayonnaise, parmesan cheese, cayenne pepper, and lemon juice until combined. Spread the mayonnaise mixture over the top of the fish. Use it all.
Next, place the crackers in a Ziploc bag and pound them until you have fine crumbs. Sprinkle the crackers crumbs all over the mayonnaise topping. You want a substantial amount of crackers to form the crust, not just a light sprinkle. Don’t be shy.
Bake for 15 minutes or until the salmon is cooked through and the crust is golden. Remove from the oven.
Remove from the oven and plate salmon pieces or use a spatula to cut the fillet into 4 pieces before serving. Garnish with some chopped fresh parsley if you like. Serve immediately.
The foil is my secret weapon. I don't need to de-skin the salmon. Instead, I run my spatula between the cooked fish and the skin and the fish comes right off. The skin sticks to the foil instead. Then you just toss out the foil after dinner.