GRILLED FRITTATA WITH ZUCCHINI, LEEKS, CRèME FRAîCHE AND HARISSA

Steps:

• Light a grill or preheat a grill pan; if you're using a charcoal grill, leave one spot cooler for indirect cooking. Lightly brush both sides of the zucchini and the leeks with olive oil and season with 1/2 teaspoon salt and pepper. Grill the zucchini over high heat, turning once, until nicely browned and tender, about 2 minutes per side. Transfer to a work surface, let cool slightly and slice crosswise 1/2 inch thick.
• Grill the leeks over high heat until grill marks form, about 2 minutes per side, then move the leeks to a cooler part of the grill and grill over moderately low heat, turning occasionally, until just tender, about 15 minutes. Transfer the leeks to a work surface and let cool slightly. Remove the outer leaf and thinly slice the leeks crosswise, discarding any tough dark green pieces.
• Turn the grill burners to moderate heat or, if you're using a charcoal grill, let the hot coals cool slightly. Brush a seasoned 12-inch cast-iron skillet generously with olive oil and set it on the grill.
• In a large bowl, whisk the eggs with 1/4 cup of the crème fraîche and remaining 1 teaspoon salt. Stir in the cooled vegetables. When the skillet is hot, carefully pour in the eggs and vegetables. Using a spoon, carefully dollop the remaining 2 tablespoons of the crème fraîche and the 2 teaspoons of harissa around the top of the eggs. Close the grill and cook the frittata for about 15 minutes, moving the skillet a few times to make sure it's evenly heated, until the eggs are puffed and set.
• Let the frittata cool slightly, then garnish with the basil leaves. Slice the frittata into wedges and serve, passing more harissa at the table.