In a pan, place the milk, condensed milk, cornstarch and milk. Mix well and place over medium heat, when it boils, leave for 8 minutes on the heat, always stirring. We want the cream to be thick and not brittle.

Turn off the heat and stir for a few minutes to cool. Let rest at room temperature.

In a container, place the semi-sweet chocolate in pieces and microwave for about 1 minute with 30 second intervals, or until melted.

Add the remaining cream and mix well until you obtain a creamy ganache. Let cool to room temperature, stirring occasionally.

On a dessert platter, spread ganache on the sides of the dish using a spoon. Pour all the nest cream into the dish.

Place spoonfuls of ganache on the nest cream in circular movements, as if you were making a scoop of ice cream to create a marbled effect. Pull gently from the inside out, repeat this process several times until the dessert is well truffled.

If you have leftover ganache, save it for another recipe, or eat it with the dessert after it's ready.

Place in the freezer for 1 hour or in the refrigerator for at least 4 hours or until firm. Ready: Serve chilled accompanied by the rest of the ganache and enjoy your wonderful nest dessert with ganache.