1) Combine all of the dough ingredients, and mix and knead them, by hand, mixer, or bread machine, to make a smooth dough.
2) Place the dough in a bowl or rising container, cover it, and let it rise for about 90 minutes, until it's just about doubled in bulk.
3) Gently deflate the dough, and divide it into six pieces.
4) Round each piece into a ball.
5) Stagger the balls on a lightly greased or parchment-lined baking sheet. Cover, and let rise for about 1 hour.
6) The balls should become quite puffy. Towards the end of their rising time, preheat the oven to 350°F.
7) Bake the buns till they're a deep, golden brown, about 25 minutes. Remove them from the oven, and let them cool right on the pan.
8) When you're ready to make bread bowls, cut the top 1/3 off each bun.
9) Gently and carefully scoop out the bread inside. Reserve it to make herb-flavored crumbs, if desired.
10) Place the bread bowls on a baking sheet or platter, and set them aside while you make the filling.
11) Melt the butter in a heavy saucepan and add the flour, stirring to combine.
12) Slowly add the broth in a stream, stirring constantly to keep the mixture from becoming lumpy. If it does get lumpy, just keep stirring till it smooths out.
13) Add the half and half or milk, stirring till smooth. Bring just to a boil, then simmer gently, stirring frequently, for 5 minutes.
14) Add the chicken or turkey, salt, thyme, and sherry, stirring to combine.
15) Add the cooked, drained vegetables, stirring to combine.
16) Bring the mixture just to a simmer, and immediately spoon a generous 1/2 cup into each bread bowl. Serve immediately.