I used Grand Marnier and the filling tasted like a black forest cake filling. I also used frozen strawberries
Strawberry Glaze with Grand Marnier
2 cups fresh strawberries, washed, hulled and halved, divided
1 cup sugar
1/4 cup cornstarch
1/4 cup Grand Marnier (or other orange-flavored liqueur)
Mash 1 cup of the strawberries. Combine mashed and unmashed strawberries, sugar and cornstarch in a saucepan. Cook over medium heat until thickened, stirring constantly. Remove from heat and stir in Grand Marnier. Cover and chill. Makes about 1-1/2 cups.