Sprinkle the strawberries, rose petals, and sea salt in desired candy molds. Set aside.
In a double boiler 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 incorporated 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 over the strawberries and rose petals. Allow to cool overnight at room temperature until solidified before removing from the molds.