Preheat your oven to 200°F (95°C). In a large mixing bowl, whisk together all-purpose flour, instant dry yeast, and fine salt. In a separate bowl, combine buttermilk, granulated sugar, and softened butter, then microwave until warm but not hot. Gradually combine these mixtures and mix in the large eggs.

Continue to add flour gradually until the dough begins to pull away from the bowl. Knead the dough on a floured surface for 5-7 minutes until slightly tacky. Allow to rest for 10-20 minutes, then incorporate fresh lemon zest.

Prepare the filling by mixing granulated sugar, light brown sugar, and lemon zest until combined. Add softened butter and stir until spreadable.

Roll the dough into a 12x18 inch rectangle. Spread the filling across the rectangle, roll tightly, and cut into 12 equal pieces.

Place the rolls in a greased baking pan and cover loosely. Turn off the oven and place the pan inside to rise for 30 minutes.

Preheat the oven to 350°F (175°C) and bake the rolls for 28-32 minutes until golden brown.

Prepare the icing by mixing powdered sugar, fresh lemon juice, and melted butter until smooth.

Drizzle the icing over the rolls after cooling for 10 minutes.