1. Skin on or off is fine, and ask your fish monger to remove the bones.
2. Panko breadcrumbs are chunkier than normal ones so they make a better crust.
3. Store bought is denser than freshly grated so if you are grating your own, use more.
4. Eschalots are mini onions. They are slightly sweeter. This can be substituted with spring onions / shallots / scallions (white part) or even normal onion. You need 2 tbsp. Or use 1 1/2 tsp minced garlic.
5. Or fish stock/broth or chicken broth.
6. This step is key to ensuring your salmon comes out with a beautiful evenly golden crust, rather than with splotches of burnt bits / overcooking your salmon to get the breadcrumb to go golden.
If your oven doesn't cook evenly, you may wish to shake the tray once.
7. My salmon was 1.2 kg / 2.4 lb and 2.5cm / 1" thick at the thickest part and it was at room temperature. 20 minutes yielded a perfectly "just cooked" salmon that is very moist. Use a knife to take a peek if you want - you can cover it back up with crumbs, no one will ever know!
If your salmon is fridge cold, add 3 minute to the cook time.
8. MAKE AHEAD at home: Prepare the crumb and place in an airtight container in the fridge until required - up to 2 days ahead. Make the sauce, cool then refrigerate. On the day of, prepare the salmon according to recipe directions. Reheat sauce in microwave - 40 seconds or so. Do not put crumb on salmon then refrigerate - it will draw moisture out of the salmon and into the crumb mixture = soggy crumb. :(
TO TAKE SOMEWHERE with no oven: In Australia, many people have a Christmas Day lunch at parks and beaches. So a reader asked me how one might prepare this for a picnic. I think this will work great to take components separately and just assemble: bake salmon with just a sprinkle of salt and pepper. Cool then wrap. Toast panko crumbing (with butter, parmesan etc) for 8 min or so, shaking tray a few times so it toasts evenly, until deep golden like in the photos. Transfer immediately to container (it keeps toasting on hot tray), allow to cool then seal. Mix together mayo + mustard (equal amounts) - juicier than plain mustard which will be better with cool salmon. Make sauce and allow to cool. Thin out sauce with a bit of water so it's pourable at the temp you expect to serve it. Then on the day of, assemble the salmon just prior to serving. Salmon and sauce is best served at room temperature rather than cold. Voila! Crunchy topping!
9. I like to allow for 180 - 200 g / 6 -7 oz of fish per serving or if it is part of a larger feast. If being extra cautious / large appetites, I do 250g / 8 oz per head.
10. Lemon Cream Sauce - I know 1 1/2 cups of cream sounds like a lot, and it is! But this serves 8 people so it's about 2 tbsp of cream per person which is not very much. Also the sauce is not rich, it is tangy from the lemon and mustard and cuts through the richness of the salmon. Perfect pairing!
11. Nutrition assuming 8 servings and that all the sauce is consumed.