Stir the yeast into the water & let proof for 10 minutes. Stir in the olive oil. Combine the cornmeal, flour & salt. Whisk 2 c of htis mixture into the yeast.
Stir in the remainder & then knead for 10 minutes until smooth. Knead in the walnuts. Place in a lightly oiled bowl, cover & let rise until doubled.
Stretch or roll the dough to fit an 10 1/2" X 15 1/2" oiled baking sheet. Cover & let rise till doubled. Preheat the oven to 400F.
Just before baking, make dimples ni the surface of the dough with your knuckles & drizzle with a wash of olive oil & sprinkle with salt.
Bake for 22 to 25 minutes, until golden. Serve hot or at room temperature.
This focaccia can be served either as a snack or as a part of an antipasto or as an hors d''oeuvre. Or simply serve it in place of bread.