Combine whipping cream and 1/3 cup sugar in a small heavy saucepan; bring to a simmer (do not boil).
Remove from heat and gradually stir about 1/4 of hot mixture into yolks; add to remaining hot mixture, stirring constantly. Stir in melted sweet chocolate and Kahla.
Pour chocolate mixture into 6 (6-ounce) ungreased ramekins.
Place ramekins in a 13" x 9" x 2" pan.
Add hot water to pan to depth of 1".
Bake, uncovered, at 300 for 30 to 40 minutes or just until set.
Remove ramekins from pan and let cool on a wire rack. Cover and chill thoroughly.
Combine marshmallow cream, mini-morsels, and milk, stirring until blended. Spoon a small dollop of marshmallow mixture evenly onto each custard.
Sprinkle brown sugar over marshmallow layer.
Place ramekins in a 13" x 9" x 2" pan; fill pan with ice cubes, surrounding ramekins.
Broil 3 1/2" from heat (with electric oven door partially opened) 1 to 2 minutes or until brown sugar melts.
Remove ramekins from pan. Chill custards 5 minutes or just until brown sugar forms a crust.
Note: Ice cubes keep the custard cold while allowing the brown sugar to melt under heat.