1. Pre heat oven to 180°C
  2. Place cauliflower, cream and butter into a saucepan. Heat gently, over a low heat.
  3. Cook for 30 minutes or until the cauliflower is just soft. Remove from heat and cool slightly.
  4. In a large bowl, combine egg and egg yolks together and then lemon zest, dill and ricotta.
  5. Season ricotta mix.
  6. Strain cauliflower from cream and keep the cream aside.
  7. Take a baking dish and pour a small amount of cream over the base.
  8. Crush the cauliflower slightly with a fork.
  9. Layer lasagna sheets with a fifth of the ricotta and cauliflower and 125g torn pieces of salmon. Sprinkle parmesan over the top of each layer.
  10. Continue until 4 layers are completed. Covering the top layer with the remaining ricotta and cream.
  11. Bake for 25 to 35 minutes or until lasagna is cooked through and golden.
  12. To serve, cut into desired pieces and garnish with chervil and salmon roe.