first chop the agar agar strands in small pieces and soak them in warm water for 10 mins.
rinse, peel and chop the mangoes. add the chopped mangoes in a blender and make a smooth puree. keep the mango puree aside.
mix cream, milk and sugar in a pan or sauce pan and keep it on the stove top. stir with a wired whisk. keep on stirring at intervals while the cream mixture comes to a gentle boil. the sugar should also dissolve completely.
Also at the same time, keep the agar agar and water solution on the stove top. keep on stirring the agar agar solution and let it cook till the agar agar strands are dissolved completely.
the cream+milk+sugar mixture should just gently come to a boil. switch off the flame.
mix the hot agar agar solution into the hot cream+milk+sugar mixture and stir very well with a wired whisk.
wait for about 5 mins till the panna cotta mixture becomes less hot. then add the mango puree and vanilla extract. mix very well with the wired whisk.
pour the mango panna cotta in serving bowls. cover the serving bowls with a lid or aluminium foil/plastic wrap. let the panna cotta become warm. then place the bowls in the refrigerator for 4 to 5 hours till the panna cotta is set.
while serving, top with some chopped mango pieces or garnish with mint leaves and serve mango panna cotta chilled.