Dark green, gray green, and yellowy green were always good colors for me. When I was a kid I loved wearing forest green tights. Capezio made excellent ones, thick and sweaty (this was part of my own private school uniform, even though I never went to private school). I’ve got number-color synesthesia, and most greens were a number 8. Pastel greens, for some reason, were not included. They had no number.
When I take an early evening walk in the woods, I surround myself with deep green and dark green, which starts to go gray as the night moves in. Exciting. And then it all goes black, and it’s beyond time to head home. That’s when the creeping critters come out.
Broccoli, spinach, kale, and Swiss chard are dark green, and so is the dark and shiny common zucchini we find in the markets this time of year. If you poke around your farmers market now, you’ll find other things that look like zucchini, that seem like they should be zucchini.
What is commonly called Romanesco zucchini is actually a different-looking zucchini-like squash. It’s speckled light gray-green, with lighter green raised ribs. It’s also called costata Romanesco, and costata means rib in Italian. I always look for it in early June. It’s dense and not as watery as dark green zucchini. And it has actual taste. Take a bite raw and you’ll see. It’s a little nutty. It almost tastes cooked even when it’s not. I love it in a pasta sauce. It doesn’t break down into a mush, and layered in a tart, like the one I made here, it’s less likely to get the crust soggy.
Romanesco is a cocozelle squash, a totally different cultivar from zucchini. Cocozelle have been grown in Italy since the 1500s. Romanesco is a variety of cocozelle that became popular here around the 1990s. There are now other varieties of cocozelle grown in the U.S. by curious farmers. You might run across one called Bravada, or Cassia, or Flaminio. But Romanesco is what you’re most likely to find, and if you see it, in June or July, I really suggest you buy it.
I love marjoram with all types of zucchini and summer squash, so I went with it for this thin torta. Its flowery sharpness lifts the vegetable’s elusive flavor, making it more substantial. Onion is also important, not only for depth but also as a good glue for a flat, eggless tart. Acidic hits from lemon are often helpful with zucchini and its cousins, but I didn’t want any here. I wanted mellow, with only the slight sharpness provided by grana and a green herb.
This is a wonderful time of year for me, produce-wise. Before all the reds and purples show up in the market, we’ve got many nice shades of green to play with.
If you’d like to make this torta with regular zucchini, I’d suggest giving it a light salting and then letting it drain on paper towels for about ½ hour.
Romanesco Zucchini Tart with Mascarpone and Marjoram
For the crust:
2 cups all-purpose flour
A big pinch of sea salt
A few big grindings of black pepper
About 1 teaspoon sugar
¼ cup extra-virgin olive oil
⅓ cup dry vermouth
For the top:
Extra-virgin olive oil
1 large summer onion, thinly sliced, using all the tender green stem, too
Sea salt
Black pepper
A few scrapings of nutmeg
½ cup of mascarpone, at room temperature
A splash of milk
½ cup grated grana Padano cheese
3 medium Romanescos, sliced into very thin rounds (it’s important they be thin, since they go into the tart raw)
About 6 or 7 marjoram sprigs, the leaves lightly chopped, plus some whole leaves for garnish
1 egg
To make the crust, put the flour into a food processor. Add the salt, black pepper, and sugar, and give it a few pulses, just to distribute everything. Drizzle in the olive oil and the vermouth, and pulse several times until you have a mass of damp clumps that stick together when you press them with your fingers. If it all seems too dry, add a little more vermouth and pulse again. Turn the dough out onto a work surface, and knead it a few times until it forms a ball. Wrap it in plastic, and let it sit, unrefrigerated, for at least an hour before you want to make the tart (you can let it sit all day if you like).
To start your filling, sauté the onion in a little olive oil over medium heat until it’s soft but hasn’t taken on much color. Season it with salt, black pepper, and a little nutmeg. Let it cool.
In a small bowl, whisk the mascarpone with a little milk, just to smooth it out. Add the grana Padano, and season with salt. The mixture should be thick but pourable. Add more milk if needed.
Preheat the oven to 425 degrees.
Rub a sheet pan with a little olive oil. On a work surface, roll the dough out into an approximately 8½-to-9-inch circle (no need to oil the work surface; the dough won’t stick). Place it on the sheet pan. Smear on the onions, leaving about an inch free all around the edge. Layer on the Romanesco in slightly overlapping circles, and season with salt and black pepper. Drizzle with a little olive oil, and scatter on the marjoram. Drizzle on the mascarpone. It doesn’t need to cover the Romanesco completely; spotty is fine. Stick the tart in the refrigerator for about 5 minutes, so it can firm up.
Drop the egg into a small bowl. Add a drizzle of water, a squirt of olive oil, salt, and a little sugar. Mix well.
Make a small, pleated edging all around the tart, and press on it lightly to make sure it stays put. The rim should be about ½ inch wide. Brush the rim with the egg wash, and stick the tart in the oven until the crust is golden and the top is set, around 15 minutes. Garnish with fresh marjoram leaves, if you like. Serve hot, warm, or room temperature. I especially like this tart with a glass of Italian rosé. The Puglian Tormaresca Rosata made from the Negroamaro grape has more body than most Provençal wines and a much deeper pink, like cranberry juice. I think, pairs well with the herbs in this tart.