In a large bowl, stir together 1/2 cup warm water (105º to 115º), yeast and generous pinch sugar; let stand until foamy, about 15 minutes. (If mixture doesn’t foam, start over with new yeast.)

In a second bowl, whisk together remaining tablespoon sugar, flour and salt. Add flour mixture, milk and butter to yeast mixture; mix together to form soft dough. Turn out dough onto lightly floured surface and knead until dough is smooth and elastic, about 10 minutes.

Divide dough into 3 equal pieces. Knead olive paste into 1 dough piece. Knead prosciutto into a second dough piece. Leave third dough piece plain. Brush 3 medium bowls with oil, then turn doughs in bowls to coat. Cover bowls tightly with plastic wrap and let doughs rise in a warm, draft-free place, until doubled in bulk, about 2 hours.

On a lightly floured surface, roll out olive dough into a 12-inch round, then cut into 6 wedges. From wide end of wedges, roll up dough so that point wraps around outside. Arrange point-down and at least 2 inches apart on a baking sheet.

Cut prosciutto dough into 6 equal pieces, then shape into balls. Arrange on baking sheet with olive rolls, at least 2 inches apart. Loosely cover doughs with plastic wrap.

Turn out plain dough onto a lightly floured surface; roll into a 7- x 10-inch rectangle with long end facing you. Leaving a 1/4-inch border, sprinkle dough with bell pepper, then, beginning with the long edge closest to you, roll dough into a log; pinch together seam where long side meets roll to seal. Cut log crosswise into 6 pieces. Arrange on a second baking sheet, seam-side down and at least 2 inches apart. Loosely cover with plastic wrap. Let doughs rise in a warm, draft-free place 45 minutes to 1 hour.

Heat oven to 350º with racks in middle and lower third. Brush tops of rolls with oil. Dust proscuitto rolls with cornmeal, if desired. Sprinkle bell pepper rolls with pinch black pepper, then slash tops lengthwise with 1 or 2 shallow cuts. Bake, rotating pans halfway through, until rolls are lightly golden and sound hollow when tapped on bottom, 25 to 30 minutes. Transfer rolls to wire rack; let cool completely.