Ingredients

• 2 ¼ cups Warm Water (100–115°F)
• 2 tsp Active Dry Yeast
• 2 tsp Sugar
• 5 cups Unbleached White All-Purpose Flour
• 6 Tbsp Extra-Virgin Olive Oil, divided
• 1 Tbsp Kosher Salt
• 1 Tbsp Unsalted Butter

• ½ bunch Asparagus
• 3 lengthwise slices Red Onion
• 3-4 sprigs fresh Parsley
• 1 Tbsp Flaky Sea Salt

Instructions

1. Pour warm water into a large bowl and sprinkle with yeast and sugar. Whisk to combine and set aside until foamy, about 5 minutes. 

2. Add flour, 1 tablespoon olive oil and kosher salt. Stir with a silicone spatula or wooden spoon to form a shaggy dough ball. Drizzle with 2 tablespoons olive oil and turn it with the spatula to coat completely. Cover bowl tightly with plastic wrap and chill until the dough is doubled in size and bubbly, at least 8 hours and up to 24 hours. (Alternatively, you can leave the dough at room temperature to rise for 3-4 hours, although the flavor will be less developed.)

3. Grease the bottom of a 9 x 13-inch baking pan with butter and then drizzle with 2 tablespoons olive oil. Uncover dough, and, with oiled hands, lift and fold the edges in toward the center of the bowl to deflate and form a very loose ball. Transfer to the prepared pan and turn to fully coat in oil. Set in a warm spot, uncovered, to proof until the dough is very bubbly and spreads to mostly fill the pan, 1 ½-2 hours. 

4. Preheat oven to 450°F with a rack positioned in the bottom third.

5. Use your fingertips to create deep indentations all over and stretch the dough close to the edges of the pan. Decorate the top of the dough with vegetables, as desired. Brush vegetables and exposed dough with the remaining 1 tablespoon of oil and sprinkle with flaky sea salt. Bake on the lower oven rack until the focaccia is deeply browned and the vegetables are tender and browned at the edges, 25-30 minutes.

6. Use large spatulas to release the dough from the bottom of the pan and transfer to a cooling rack until it stops steaming. Then cut into slices and serve warm or at room temperature.