Place pastry on a sheet pan lined with parchment paper; refrigerate until ready to use. Preheat oven to 425°F. Heat olive oil in a large skillet over medium to low heat; add onions and garlic. Sauté until onions are limp and there is almost no moisture remaining in the skillet. Add salt, pepper, wine and thyme. Continue cooking for another 6-8 minutes, until onions are lightly browned. Remove from heat. Using a sharp paring knife, cut the pastry sheet into four equal pieces and score a 1/4-inch-wide border around each pastry piece. Prick the pastry inside the score lines with the tines of a fork. Sprinkle half of grated Parmesan on pastry, staying inside the scored border. Place the onion mixture on pastry, again staying within the scored edge. Crumble the goat cheese on top of the onions. Place a slice of tomato in the centre of each tart. Brush the tomato lightly with olive oil and sprinkle with basil, salt, and pepper. Top with remaining Parmesan. Bake for 20-25 minutes, until the pastry is golden brown. (The scored edge will rise up while the filling keeps the middle weighed down, creating the tart shell.) Serve hot or warm. Serves 4.