In a small bowl, whisk together the warm water, half and half, yeast and sugar. Let proof for 10 minutes.

Meanwhile, in a large bowl cut in 3 tablespoons of butter in the flour until combined. Stir in the salt, baking powder and 1 egg. Stir in the yeast mixture. If using a stand hook, knead with the dough hook for about 5 minutes. Or alternatively, you can hand knead the dough.

Form the dough into a ball and place in a greased bowl. Melt the remaining 2 tablespoons of butter on pour on top. Cover with plastic wrap and let set 1 to 1 ½ hours, or until doubled in size.

Turn the dough out and cut into 6 equal pieces. Form into discs and slightly dome the middle. Place on a greased cookie sheet. Cover with plastic wrap and let rise in a warm place for 45 minutes.

Brush the remaining egg on top of the buns and sprinkle with sesame seeds.

Bake in a preheated oven to 375 degrees F. for about 15 to 20 minutes, or until golden brown. Let cool on a wire rack.