Ingredients

• 2 cups bread flour, plus extra for dusting work surface
• 1 teaspoon instant yeast
• 1 teaspoon table salt
• 1 tablespoon olive oil, plus additional oil for brushing dough and greasing hands
• 1 cup water, warm (about 110F)
• 2 tablespoons olive oil
• 2 lbs yellow onions, sliced 1/4 inch thick
• 4 garlic cloves
• 1/2 teaspoon table salt
• 1 teaspoon brown sugar
• 2 teaspoons balsamic vinegar
• 1 tablespoon water
• 1/2 teaspoon ground black pepper
• 1/2 cup nicoise olive, pitted, chopped coarse
• 8 anchovy fillets, rinsed, patted dry, chopped coarse
• 2 teaspoons fresh thyme leaves, minced
• 1 tablespoon marjoram leaves, minced (optional)
• 1 teaspoon fennel seed (optional)
• 1 tablespoon fresh parsley leaves, minced (optional)

Instructions

1. In workbowl of food processor fitted with plastic dough blade (can use metal blade if necessary), pulse flour, yeast, and salt to combine, about five 1 second pulses. With machine running, slowly add oil, then water, through feed tube; continue to process until dough forms ball, about 15 seconds.

2. Generously dust work surface with flour. Using floured hands, transfer dough to work surface and knead lightly, shaping dough into ball.

3. Lightly oil 1 quart measuring cup or small bowl, place dough in measuring cup, cover tightly with plastic wrap, and set aside in draft-free spot until doubled in volume, 1 to 1 1/2 hours.

4. While dough is rising, heat oil in 12 inch nonstick skillet over high heat until shimmering but not smoking. Stir in onions, garlic, salt, and brown sugar and cook, stirring frequently, until moisture released by onions has evaporated and onions begin to brown, about 10 minutes.

5. Reduce heat to medium-low and cook, stirring frequently. After 15 minutes, remove garlic cloves, mince them and then return them to the pan, along with the balsamic vinegar. Stir and continue cooking for 5 more minutes, until onions have softened and are medium to golden brown. Off heat, stir in water; transfer to bowl and set aside.

6. When dough has doubled, adjust oven rack to lowest position, set baking stone on rack, and heat oven to 500°F.

7. Remove dough from measuring cup and divide into 2 equal pieces using dough scraper. Working with one piece at a time, form each piece into rough ball by gently pulling edges of dough together and pinching to seal. With floured hands, turn dough ball seam-side down. Cupping dough with both hands, gently push dough in circular motion to form taut ball. Repeat with second piece.

8. Brush each lightly with oil, cover with plastic wrap, and let rest 10 minutes. Meanwhile, cut two 20 inch lengths parchment paper and set aside.

9. Coat fingers and palms of hands generously with oil. Using dough scraper, loosen 1 piece of dough from work surface. With well-oiled hands, hold dough aloft and gently stretch to 12-inch length (like a very large breadstick). Place on parchment sheet and gently dimple surface of dough with fingertips. Using oiled palms, push and flatten dough into 14x8 inch oval.

10. Brush dough with oil and sprinkle with 1/4 teaspoon pepper. Leaving 1/2 inch border around edge, sprinkle 1/4 cup olives, 1 tablespoon chopped anchovies, and 1 teaspoon thyme evenly over dough, then evenly scatter with half of onions. Sprinkle with fennel seeds and marjoram, if using.

11. Slip parchment with tart onto pizza peel (or inverted rimless baking sheet), then slide onto hot baking stone. Bake until deep golden brown, 13 to 15 minutes. While first tart bakes, shape and top second tart.

12. Remove tart from oven with peel or pull parchment onto baking sheet; transfer tart to cutting board and slide parchment out from under tart. Cool 5 minutes; sprinkle with 1 1/2 teaspoons parsley, if using. Cut tart in half lengthwise, then cut crosswise to form 8 pieces; serve immediately. While first tart cools, bake second tart.