Manual/Mixer Method: In a small bowl, work together the biga ingredients -- 1 1/2 cups flour, 1/2 cup water and 1/4 teaspoon instant yeast -- till they're well-combined, but not or kneaded. Cover the bowl, and allow the biga to rest overnight at room temperature.
Next day, combine the biga with the remaining dough ingredients in a large mixing bowl, stirring till the dough becomes cohesive, then kneading or stirring vigorously in the bowl till it becomes smooth. This is a very slack (wet) dough; don't try to add enough flour to make it kneadable on a work surface. If you have an electric mixer, knead it with the flat beater attachment for 5 to 8 minutes. If you're mixing by hand, use a bowl scraper and your hands to work it as best you can. It'll become smooth and will hold its shape somewhat, but will be very sticky. Cover the bowl and allow the dough to rise for 1 hour.
Bread Machine Method: Place all of the biga ingredients into the pan of your bread machine, program the machine for Manual or Dough, and press Start. Cancel the machine as soon as the ingredients have formed a rough ball of dough, and all of the flour is incorporated.
Next day, add the remaining dough ingredients, program the machine for Manual or Dough, and press Start. Allow the machine to complete its cycle.
Shaping: Lightly grease a clean work surface, and transfer the dough to the greased work surface. Shape it into a rough 8 x 14-inch oval, and transfer it to a lightly greased baking sheet. (A half-sheet pan -- 18 x 13 inches -- is ideal for this. If you don't have a pan at least this large, divide the dough in half, make a couple of 4 x 14-inch ovals, and place them on two separate baking sheets.) Brush the top of the dough lightly with olive oil, and cover it; an acrylic dough cover is a great help here. If you use greased plastic wrap, it'll probably stick, so just be gentle pulling it off when the time comes.
Allow the dough to rise till it's very puffy and bubbly, about 3 hours at room temperature. Halfway through the rising time dimple the surface with your fingertips, assertively enough to leave marks, but not so vigorously that you deflate the dough completely.
Preheat the oven to 425°F. Spritz the surface of the dough with warm water, and bake it for 15 to 20 minutes, till it's golden brown. Remove it from the oven, and allow it to cool. Wrap it loosely in plastic overnight, or in a paper bag.
Assembly: Prepare the topping by combining the minced garlic cloves, melted butter, olive oil and a pinch of salt. Just before serving, cut the bread (or the two loaves, if you've made two) in half lengthwise, like you're going to make a giant sandwich. Spread the cut halves with the garlic mixture. Bake the bread in a preheated 400°F oven for about 10 minutes, or until the topping is bubbly and the edges of the bread are starting to brown. Remove the bread from the oven, and sprinkle it immediately with the grated Parmesan and parsley, if desired. Yield: about 24 servings.