Heat the milk with vanilla in a medium saucepan over medium heat until just below a simmer.
Slowly pour hot milk to the egg mixture and then return the mixture to the saucepan. Whisk mixture constantly over medium heat until thickened and glossy for about 2 minutes.
Stir in the butter then cool to room temperature. Chill completely until ready to use.
Preheat the oven to 350°F/180°C. Lightly grease 8 mini tart pans.
Cut the peach halves in thin slices. Bloom the gelatin powder in 1 tablespoon cold water. Once bloomed, add 2 tablespoons hot water to dissolve the gelatin. Add the gelatin mixture in the peach syrup. Set aside.
Once the crusts are cooled, fill it with the pastry cream. Carefully arrange the peach to form a flower. Brush this with the peach syrup mixture.
Cool to set the gelatin and cream. Serve.