Combine the various components for the brunch on platters, in sauce boats and plates as desired. Garnish with dill, lemon wedges, and so on.
Serve with a pepper mill on the side.
If desired, make sandwiches as follows: 1 slice of toasted, buttered bagel smeared with cream cheese, an onion slice, sturgeon and/ or salmon, capers, a few drops of lemon juice