Stir together the flour, yeast, sugar, lemon zest, in a stand mixer.
Heat the beer to 120°F (Always defer to the liquid temperature listed on the package of yeast, regardless of what the recipe says. Your yeast package says 105°F? Heat the liquid to that temperature!)
Add the warmed beer to the stand mixer, mix until incorporated.
Add the butter, vanilla and salt. Continue to beat until the dough is no longer sticky and gathers around the hook, about 8 minutes.
Add dough to a large, lightly oiled bowl. Cover and allow to rise until doubled in size, about 1 hour.
Add dough onto a lightly floured surface. Roll into a large rectangle about 9x13 inches in size.
Add all filling ingredients (except the blackberries) to a bowl, mix until well combined.
Spread the filling evenly across the dough, sprinkle evenly with blackberries.
Starting with the long end, roll the dough tightly into a long log. Cut into 12 rolls about 1 ½ inches wide.
Add the rolls tightly into a baking dish, cut-side up.
Allow to rise until doubled in size, about 30 minutes.
Bake at 350°F until golden brown, about 40 minutes.
Beat together the butter and cream cheese until well combined. Add in the remaining ingredients, then beat until light and creamy.
Frost before serving. Serve within 10 hours of making.