Spring onion kebabs with romesco celebrate the season in Spanish style

Every year about now, my heart skips a beat the first time I spy those gorgeous spring onions in farmers markets and grocery stores. You know the ones, I hope? They look like scallions that have gotten as swole as a tech bro.

And every year, I think to myself: Why am I not in Spain right now? Or, more accurately, why wasn’t I in Spain a month or two ago? That’s when restaurants in Catalonia host dinners celebrating calçots, their version of spring onions that are planted twice to bulk up their greens, too. At these calçotadas, the onions get charred on the grill by the hundreds, if not thousands, then wrapped in newspaper to steam and served to hungry diners who peel off the blackened exteriors and swipe the sweet, soft interiors through the classic Spanish romesco sauce. Wine is involved.

Here, the spring onions don’t come until later in the year, but I’m always tempted to host a calçotada of my own. Inspired by that impulse, I came up with a recipe that pays tribute to the delectable combination of grilled onions and romesco.

In the spirit of a weeknight dinner, I threaded some more heft (in the form of zucchini, shishito peppers and halloumi cheese) onto skewers along with those onions, and I stopped well short of charring them as black as the Spaniards do. The halloumi, I realize, directs this recipe from Spain toward Greece, but I can’t resist its squeaky texture and salty flavor. (If you want, you can easily sub in tofu or paneer.)

To make it even quicker, my streamlined version of romesco skips the roasting and peeling of bell peppers (often used as a substitute for the dried nora peppers traditionally included), and cooks them right on the grill, along with most of the other sauce ingredients, before pureeing them. Might as well make the grill do double duty while you’ve got it fired up, right?

For all of you who’d rather stay inside, either because you don’t have a grill or you prefer the air conditioning, all is not lost: You can make this recipe using your broiler instead.

Inside or out, you can close your eyes, inhale the aroma of onions and peppers, and dream of a calçotada.

Spring Onion and Halloumi Kebabs With Romesco

Grill skewers of spring onions, zucchini and halloumi cheese while you also char the ingredients for the classic Spanish romesco sauce that will accompany them. The idea comes from the Catalan calçotada, an annual celebration of spring onions at which they’re charred over a fire and served with lots of romesco (and lots of wine). Halloumi elevates this to main-course status, but the cheese is also particularly high in sodium; see Substitutions for lower-sodium alternatives. For broiling instructions, see Variations.

For the romesco:

High-heat cooking oil, such as canola, for the grill

2 medium red bell peppers (10 ounces total), stemmed, cored and cut into 2-inch chunks

1 large plum tomato (4 ounces), quartered

3 large garlic cloves (unpeeled)

2 tablespoons olive oil

¼ teaspoon fine salt, plus more as needed

1 to 2 small slices sourdough bread (1 ounce)

½ cup (2½ ounces) roasted, unsalted almonds

½ teaspoon sweet or hot smoked Spanish paprika (pimentón dulce or picante)

¼ teaspoon ground cayenne pepper (optional)

1 tablespoon sherry vinegar or red wine vinegar, plus more as needed

For the kebabs:

1 medium zucchini (8 ounces), cut into 12 chunks

1 pound halloumi cheese, cut into 12 chunks

12 shishito peppers

6 spring onions (see Notes and Substitutions), trimmed

1 tablespoon olive oil

¼ teaspoon fine salt, plus more as needed

¼ teaspoon freshly ground black pepper

Have six long wooden, bamboo or metal skewers ready. (If using wooden or bamboo skewers, soak them in water for at least 30 minutes before making the kebabs. If using metal skewers, there’s no need to soak.)

Prepare the grill for direct heat. If using a gas grill, set it to 450 degrees. If using a charcoal grill, fill a chimney starter with charcoal, light it, and when the coals are white-gray with ash, pour them onto the charcoal grate, adding more charcoal, if necessary. Put the lid on the grill, making sure the vents are fully open. When all of the coals are gray and hot, about 15 minutes, your grill should be at medium-high heat. (Use a grill thermometer, or test the heat by holding your hand, palm-down, about 4 inches from the grate, making sure that nothing flammable, such as clothing, is near the heat. If you can hold it there for about 4 seconds, the heat should be at medium, or about 450 degrees. Pull your hand away from the heat before it gets painful.) Make sure the cooking grates are clean, then use tongs to dip a folded paper towel in the cooking oil and lightly apply a thin layer of oil all over the grill grates.

Make the romesco: In a medium bowl, toss the bell peppers with the tomato, garlic, oil and salt. Transfer to a grill basket or a heatproof wire rack, and grill over high heat, shaking frequently, until the vegetables are lightly charred all over, about 5 minutes. Pick out the garlic, and transfer the rest of the basket contents to a food processor or blender. Squeeze the garlic out of its peels into the food processor.

Grill the bread until lightly charred, 1 to 2 minutes per side. Tear into chunks and add to the food processor. Add the almonds, smoked paprika, cayenne, if using, and vinegar. Puree until mostly smooth but with a little chunky texture, scraping down the sides partway through as needed. Taste, and season with more salt and vinegar, as desired. You should have about 2 cups.

Transfer the romesco to a large platter, swooshing it across.

Make the kebabs: Thread a chunk of zucchini onto one of the skewers, followed by a chunk of halloumi and a whole shishito. Repeat with another piece of zucchini, halloumi and a shishito, and end with a spring onion, threading it through the bulb lengthwise if possible. Repeat with the remaining skewers and ingredients.

Drizzle the kebabs with the oil, and lightly season with the salt and pepper.

Transfer to the grill and grill until lightly charred on the bottom, about 3 minutes. Flip the skewers over and continue grilling until lightly charred on the bottom, another 3 minutes. Arrange the kebabs on top of the romesco on the platter.

Serve warm or at room temperature.

Yield: 6 servings

Variations: To make this in the broiler, arrange all the ingredients for the romesco sauce, except the spices and vinegar, on one large sheet pan and the kebabs on another large sheet pan. Arrange an oven rack in the position closest to the broiler, preheat the broiler to HIGH and broil the romesco ingredients for about 2 minutes, or until the bread starts to lightly char on one side, then transfer it to the food processor. Continue broiling the remaining ingredients for 3 to 4 minutes per side, or until they are lightly charred on both sides. Continue following the recipe for the sauce. Broil the kebabs for 3 to 4 minutes, or until lightly charred on top, then flip them over and broil for another 3 to 4 minutes, or until lightly charred on the other side.

Notes: While the terminology is often confused, spring onions – limited to their season – are larger and more bulbous than green onions/scallions.

Make ahead: If using wooden or bamboo skewers, soak them in water for at least 30 minutes before grilling.

Storage: Refrigerate the kebabs and romesco sauce separately for up to 4 days. The romesco can be frozen for up to 3 months.

Where to buy: True spring onions, much larger than scallions, can be found at farmers markets and at some well-stocked supermarkets when in season.