1Trim the ends off two bunches of asparagus. Cut the trimmed asparagus to the height of your pan or mousse ring, keep the stalks that you trimmed off. Bring a pot of salted water to a boil. Cook the asparagus tips and the stalks in the salted water. After about 5 minutes, remove the tips. You want them to be just barely cooked and still have a decent crunch. Continue to cook the stalks for about 20 minutes, so they are very tender. Cut the asparagus tips in half lengthwise then arrange them standing up around your pan or mousse ring
2Pour the cream into a saucepan and add the agar. Mix and boil for 30 seconds so the agar dissolves then remove from the heat. Mash the goat in a bowl, then add the chopped spring onion, salt, and pepper. Add the cream and stir quickly. Pour into mousse ring. Set aside.
3Drain the cooked asparagus and press them to get rid of any additional cooking water. Fry them in 10g of butter in a skillet over high heat for 5 minutes. Puree asparagus and 15 cl of cream in a blender. Add salt and pepper. Pour the cream into a saucepan and add 1 teaspoon of agar. Boil for 30 seconds, then stir well and pour it over the goat cheese layer.
4Let chill in the refrigerator for at least 3 hours, overnight is better. Carefully remove the mousse ring. Arrange the smoked salmon and salmon roe on the charlotte, serve.