In a bowl, toss strawberries and liqueur or orange juice; cover and refrigerate.
To make chocolate mousse: In a small saucepan, mix water with 2 tbsp of the sugar.
Bring to boil; reduce heat and simmer 1 minute.
Place chocolate pieces in container of electric blender.
Immediately add hot sugar mixture.
Blend until chocolate is melted and smooth.
In medium bowl, whip 3/4 cup of the cream to form stiff peaks.
With rubber spatula, fold chocolate into cream to blend thoroughly.
Cover and refrigerate until firm, at least 2 hours or up to 3 days.
Just before serving, whip the remaining 3/4 cup cream to form soft peaks.
Beat in the remaining 1/2 tbsp sugar and the vanilla.
In four 10 to 12 oz stemmed wine glasses or in dessert bowls, layer mousse, whipped cream and strawberries, dividing equally.
Garnish with mint sprigs.