I've been trying to do a little research on Romanesco Broccoli and haven't come up with much. But here's a few tidbits of information. It is an heirloom, seemingly (you know about getting info from the web) first described in print in the 16th century. Did you know that broccoli and cauliflower were probably selected from wild brassicas way back in 400-600 BC in the eastern Mediterranean?
Depending on what language you are speaking, Romanesco is variously referred to as cabbage, cauliflower, or broccoli. In the opinion of many it is none of the aforementioned. Even the botanists can't agree, some place it within the Brassica oleracea Botrytis group (cauliflower) and some within the B. oleracea Italica group (broccoli). From a cooks point of view (i.e. mine) it is neither. I tend to cook it like cauliflower because of it's texture, but in terms of flavor it is unique. I'm really no good at analyzing and describing flavors, so I recommend that you try it yourself. What I can say about the flavor is that it is milder than either broccoli or cauliflower, and I love it.
Romanesco is not to be confused with Broccoflower which is a green cauliflower (some sources say it's a broccoli/cauliflower cross). The two vegetables look superficially alike, both being green, but Romanesco has a stronger fractal appearance and very pointed florets. I've grown and cooked both and my preference is for Romanesco.
New varieties of Romanesco have been developed in recent years (many F-1) that overcome a few problems that face commercial growers of this vegetable. One "problem" is that happy Romanesco plants can produce massive heads that are difficult to sell (I grew a 5 pound head one year). Another problem is that the open pollinated heirloom varieties tend to have heads of varying sizes and maturity dates. Hmm, uniformity of size and harvest date, not really something that I consider an advantage in my own garden.
Romanesco plants are quite large, the plants in my garden now are about 3 feet high and as wide. I planted them 18 inches apart and they appear to be happy with that spacing, but 24 inches is the recommended spacing. Perhaps if I had spaced them further apart I might have grown another 5 pounder! There are new varieties of Romanesco that have been bred to be smaller if your space doesn't allow for such large plants. All varieties need a fertile soil that has a neutral pH and they need regular water.
My second head of Romanesco was turned into soup this weekend. Here's the recipe.
Spiced Romanesco Broccoli Soup
2 tbs unrefined peanut oil
2 curry leaves (one curry leaf has many leaflets), optional
---botanical name is Murraya koenigii
1 medium onion, chopped
3 cloves garlic, peeled and lightly smashed
1/2 teaspoon garam masala (see note below)
1 head of Romanesco broccoli (about 1 pound)
---cut into florets, reserve about 24 bite size florets
---peel and dice the stem
3 small white potatoes, peeled and diced
1 quart water
1 13.5 ounce can of coconut milk
1 tablespoon fish sauce (nuoc mam nhi), optional
lime juice to taste
hot sauce to taste (I like Sriracha)
1/4 teaspoon garam masala
croutons for garnish
Heat the peanut oil in a 4 or 5 quart sauce pan over medium heat. Add the curry leaves and let them sizzle a bit, then remove and discard them. Add the onion, garlic, and garam masala to the pot, saute until the onion softens. Add the Romanesco florets (not the reserved ones), the diced stem pieces, the potatoes and water. Bring to a simmer, turn the heat to low, cover and let simmer until the vegetables are tender but not falling apart.
Meanwhile, preheat the oven to 450F. Toss the reserved florets with some peanut oil and the 1/4 teaspoon of garam masala. Arrange the florets on a baking sheet and roast them until the edges start to brown, about 7 to 10 minutes. Set aside to cool.
Puree the soup in 2 or 3 batches in a blender until very smooth. Return the pureed soup to the pot and stir in the coconut milk, the fish sauce, lime juice and hot sauce. Taste for salt, the fish sauce is salty so no additional salt may be necessary. Bring back to a simmer before serving in warmed soup bowls. Garnish each bowl with a few roasted florets and some tiny crispy croutons.
Makes about 6 servings.
Note: Garam Masala is an Indian spice blend. The one I have (Whole Foods brand) contains black pepper, cardamom, cinnamon, cloves, cumin and coriander. You could use curry powder instead, but I suspect that the turmeric in curry powder would give the soup a strange color.