Preheat the oven to 325 degrees F (165 degrees C). Grease and flour a 10-inch fluted tube pan, such as Bundt.

In a large bowl, stir together cake mix and gelatin mix. Make a well in the center and pour in eggs, oil, and blackberry wine. Beat on low speed until blended. Scrape bowl, and beat 4 minutes on medium speed. Pour batter into the prepared pan.

Bake in the preheated oven for 40 to 45 minutes, or until a toothpick inserted into the center of cake comes out clean.

Meanwhile, make glaze: In a small bowl, stir together confectioners’ sugar and 1/2 cup blackberry wine.

Pour 1/2 of blackberry wine glaze over the top of cake while still warm. Let set for 10 minutes then remove cake from pan. Allow cake to cool fully before pouring the remaining glaze on top.