In a bowl you put some water and you pour the powdered gelatin in. Stir and leave it there for 5 minutes. Defrost the raspberries and mash them in blender. Then pass them through a thin strainer and put them in a small pot with the sugar. Then boil them in medium heat for 5 minutes. Add the vanilla and the shattered gelatin and stir well. Put the jelly aside so that its temperature can be reduced a bit.
In a bowl with some water, put the gelatin in. Stir and leave it for 5 minutes. Pour the fresh crème with the milk and the sugar in a small pot in medium heat until they boil up but without reaching the boiling point. Remove from the fire and add the vanilla, the gelatin and stir well. Split the half quantity of panna cotta in individual bowls and put them in the refrigerator. When panna cotta thickens pour over the half amount of jelly and put it back in the refrigerator. Repeat the procedure for two more times until you succeed the two colors you see.