A light, sweet, gelatinous pudding of very delicate texture, totally unlike a typical gelatin dessert Jello it is not. Have large cooled bowl or (preferably) 23 cm x 23 cm glass dish ready for gelatin mixture. Add agar-agar to boiling water and stir until thoroughly dissolved. (Watch for burning on bottom.) At this stage, agar-agar will impart noticeable odor, but it does not carry through to finished dish. Add evaporated milk and sugar; bring back to boil and boil for 1 minute, stirring constantly. Add almond extract. Slowly add hot water, continuing to stir until sugar is completely dissolved. As soon as mixture returns to boil, turn off heat. Pour mixture into bowl for setting. When it has cooled slightly, cover and refrigerate for at least 2 hours. Turn jellied mixture out onto flat plate, then cut it in 3 cm squares. Place squares in individual serving bowls with Mandarin orange wedges and their juice. Cover and return to refrigerator until ready to serve.