In a small saucepan, over medium-low, heat the frozen raspberries and red wine.

Reduce the liquid to 3-4 tablespoons by continuing to simmer on medium low heat for about 30 minutes. Once the mixture has been reduced, remove the raspberry wine reduction from the burner and allow to cool.

Whip the softened butter in a mixing bowl, using the whisk attachment until fluffy (about 1 minute).

While the mixer is running, slowly add the cooled raspberry wine reduction and white pepper. Mix until thoroughly incorporated.

Transfer to a mold or ramekin, cover and refrigerate.