Prepare the base. Pour the cream and milk into a thick-bottomed saucepan. Heat, but do not boil. Turn off the stove and pour in the sugar. Stir until the crystals are completely dissolved.
Make panna cotta. Combine the milk and cream mixture with gelatin and mix again until smooth. Pour the resulting liquid into bowls and refrigerate for 120 minutes.
Cook the sauce. Place the strawberries in a saucepan, pour in the juice released during defrosting, sprinkle with sugar. Using a blender, turn the berries into a puree. Cook over medium heat for 5 minutes, then increase the heat, bring to a boil and cook for another 3 minutes. Stir the sauce while cooking so that it does not burn. Cool the finished strawberry sauce.
Assemble the dessert. Take the panna cotta bowls out of the fridge. Spoon the strawberry sauce over the top.