Stir together yeast and 1/4 cup water in a 1-cup measuring cup; let stand 5 minutes.
Pulse 1 cup flour, sugar, and salt in a food processor until blended. Add yeast mixture, 1 egg, and milk; pulse until blended. (Pulsing prevents mixture from overheating, which would kill yeast.) Add butter, 1 tablespoon at a time, pulsing until combined. Gradually add enough of remaining flour until dough is no longer sticky. (Dough should be smooth.)
Place dough in a well-greased bowl, turning to grease top.
Cover and let rise in a warm place (85°), free from drafts, 1 hour or until doubled in bulk. Punch dough down, and divide into fourths; shape each portion into 6 (1-inch) balls. Place on a lightly greased 13- x 9-inch pan.
Cover and let rise in a warm place (85°), free from drafts, 1 hour.
Stir together remaining egg and 1 tablespoon water; brush over rolls, and sprinkle with sesame seeds.
Bake at 375° for 15 to 20 minutes or until golden brown. Freeze up to 3 months, if desired.
Note: Rolls may also be prepared with a heavy-duty mixer.