Make the socca: In a medium bowl, combine the chickpea flour, water, 2 tablespoons olive oil, garlic, and salt and pepper. Whisk until smooth, cover, and set aside to soak for 30 minutes. Preheat the oven to 450 with a 12-inch cast-iron skillet inside.
Make the almond-herb spread: In a high speed blender, combine the almonds, garlic, miso, lemon juice and zest, nutritional yeast, ½ cup water, 1 tablespoon olive oil, and pinches of salt and pepper. Blend, adding more water and/or olive oil as needed to get your blade moving and to create a creamy, paste-like consistency. Pour into a smaller bowl and stir in the ¼ cup herbs. Taste and adjust seasonings. Place in the refrigerator while your socca cooks. When you’re ready to use the spread, you may need to thin it with a bit more water.
When the oven is preheated and your socca batter has rested for 30 minutes, remove the preheated skillet from the oven with a pot holder, add the remaining 1 tablespoon olive oil, and brush to coat the bottom and sides of the pan. Pour the batter into the pan and bake for 12 to 15 minutes, until the edges of the pancake have set. Heat the broiler and brush the top of the socca with a little olive oil if it looks dry. Broil socca for a few minutes, until its top is spottily browned. Let your socca cool a bit before assembling with the almond spread.
In the meantime, heat a drizzle of olive oil in a small skillet over medium heat, and sauté the leeks with a pinch of salt for a minute or two. When your socca has cooled, layer on the almond herb spread (you might not use it all), sautéed leeks, sliced almonds, and a sprinkle of the remaining herbs.