Preheat the oven to 400 degrees and butter a 9x13 inch pan.
Add buttermilk and 4 tablespoons butter to a liquid measuring cup. Microwave for 20 seconds at a time until butter is mostly melted. Buttermilk should be very warm but you should still be able to touch it without burning your finger (about 110 degrees).
In a large bowl, combine honey and yeast.
Whisk in buttermilk and butter mixture.
Whisk in salt and egg.
Add 2 1/2 cups flour.
Mix (by hand, or with an electric hand mixer, or you can do this in the bowl of a stand mixer fitted with a dough hook attachment) until flour is completely incorporated.
Gradually add more flour, 1/4 cup at a time, until dough comes together just enough to form a ball. (It will stick be quite sticky! You should be able to handle it with heavily floured hands.)
With floured hands, transfer to a lightly floured surface (be careful not to use too much flour as it will dry out your dough) and knead for 4-5 minutes until dough is smooth and elastic.
Divide dough into 12 equal-size pieces and roll each into a ball. Place 1 inch apart in prepared pan.
Cover pan tightly with plastic wrap and let dough rise for 10 minutes in a warm place (I place mine near the preheated oven).
Uncover, and bake in preheated oven for 15-20 minutes until golden brown on top.
Brush immediately with remaining 2 tablespoons butter and serve.