In a double boiler or two pots, set to medium-low heat, melt the cocoa butter and vanilla extract together.
Stir in the powdered sugar, powdered milk, and seeds from the vanilla bean until completely mixed together and bring the mixture to 120˚F (49˚C), no higher.
Remove from heat and whisk the mixture for a couple of minutes, then place in the refrigerator for 5 minutes.
Whisk again for a few minutes and continue the process, in and out of the refrigerator until the mixture drops to 79˚F (26˚C).
Heat again in the double boiler up to 89˚F (32˚C), no higher.
Pour the mixture into the prepared molds as it is or over whatever you have chosen to add, like nuts or fruit
Allow them to cool overnight at room temperature until solidified before removing them from the molds. Keep them in the fridge to avoid them melting