Circle B Kitchen
The original recipe called for cooking up 12 ounces of chickpeas, but most chickpeas come in 1 lb bags, so I always cook up the whole thing. The leftover chickpeas are great in salads, soups, or go ahead and make some hummus. If you would like to discard all of my good advice and use canned chickpeas for this, click on the Serious Eats link below where you will find instructions for this. Evidently, they are even more pro choice than I.
Recipe barely adapted from Serious Eats
1 lb dried chickpeas, soaked overnight in salted water*
* Chickpeas can also be prepared using the quick soak method. Cover with water in a large pot, bring to a boil, remove from heat, and let rest for 1 hour. Drain and proceed with the recipe as directed.
Place chickpeas in a large pot and cover with lightly salted water by at least 2 inches. Add unpeeled garlic, onion, and rosemary. Cover and bring to a boil over high heat. Reduce heat to a bare simmer and cook, topping up with water as necessary to keep beans submerged, until beans are very tender and creamy with no graininess left, about 2 hours. Beans can also be cooked in a pressure cooker at low pressure for 30 minutes.
In a medium saucepan, combine oil, garlic, and red pepper flakes and set over medium heat. Cook, stirring, until garlic is lightly golden, about 3 minutes. Add 3 cups chickpeas and 1 1/2 cups of chickpea-cooking liquid (I ended up using a little more than 2 cups) and bring to a simmer. Remove from heat and, using an immersion blender, blend to a smooth, saucy puree, adding more chickpea-cooking liquid if too thick. Stir in remaining 1 cup chickpeas, crushing some lightly with a wooden spoon or potato masher but leaving them mostly whole. Season with salt and pepper.
In a pot of salted boiling water, cook pasta until just short of al dente. Reserve 1 cup of pasta-cooking water, then drain pasta. Return pasta to pot and add chickpea sauce along with 1/4 cup of reserved pasta-cooking water. Set over medium heat and bring to a simmer, stirring until pasta is al dente and sauce has thickened just enough to coat pasta, about 3 minutes; add more reserved pasta-cooking water, 1 tablespoon at a time, if sauce becomes too thick. Remove from heat, stir in chopped parsley and drizzle in some fresh olive oil, stirring to blend. Season with salt and pepper. Spoon pasta and sauce into bowls, drizzle with another whirl of olive oil, some chopped parsley and grated Parmesan cheese and serve.