Soak the herring in milk for 6–10 hours, dry, cut each fillet into 3 equal parts.
Bake sweet peppers under a hot grill until black marks on all sides, put in a plastic bag, twist and leave for 15 minutes, then peel and seeds, cut into strips.
Peel and grate the ginger, add a little grated zest and all the lime juice. Season with salt and pepper.
Peel the apple from the peel and core, cut 8 sticks from the pulp. Cut 8 thick circles from the cucumber. Place apples and cucumbers in lime marinade for 30 minutes. Then take it out and dry it a little.
Marinade mixed with olive oil in a ratio of 1:1. Roll up rollmops with 3 fillings from pieces of herring: a cucumber and an apple can be wrapped with a piece of herring, and vice versa wrapped in sweet pepper.
Put the rollmops on the croutons of Borodino bread and pour dressing from oil with marinade. Serve immediately.