Follow the recipe for Basic Herb Focaccia through Step 3. While the dough rises, preheat the oven to 350°. Toast the pine nuts on a baking sheet for about 7 minutes, until golden. Let cool.
Punch down the dough, turn it out onto a work surface and knead in the nuts and Parmesan, distributing them evenly. Return the dough to the bowl, re-cover and let rise again until doubled, about 1 hour.
In a medium skillet, heat 1/4 cup of the oil. Add the onion and garlic and cook over moderately high heat for about 5 minutes. Season with the oregano and pepper. Let cool.
Proceed with Steps 5 and 6 of the Basic Herb Focaccia recipe, but before you let the dough rise, gently brush it with enough olive oil to coat lightly. Spread the onion mixture on top, leaving a 1-inch border.
Preheat the oven as directed in Step 7. Dip your fingers in flour and make many indentations in the dough. Sprinkle pepper and coarse salt on top. Proceed with Step 9, but bake the dough for 25 minutes; sprinkle the Parmesan on top and bake until golden, about 10 minutes longer.
Lauren Groveman is the author of The I Love to Cook Book: Rediscovering the Joy of Cooking for Family and Friends.