You can either soak the dried beans overnight (which is simpler, but requires forethought) or quick soak them (which is faster). Quick soaked beans won't soften as easily. They tend to have a bit of a crunch to them. Which is fine for this dish! Although, I wouldn't recommend it for something like hummus where you're going to want a more even, soft cook.You can also do this with chickpeas or other semi-soft white bean. Most white beans work incredibly well with a quick soak. If you're going to use chickpeas, though, they take a lot of time to soften. So, I'd highly recommend soaking them overnight and using a high-powered blender or food processor.
Overnight:Place dried beans in a bowl and cover with cold water. Soak overnight, or for 12-24 hours.The beans will roughly double in size, so make sure to use a large enough bowl and add enough water to accommodate this. Roughly 2-3 inches should be enough. Although it can also help to drain and refill with cold water at least once, especially if you’re soaking for more than 12 hours.
Quick Soak:Add beans to a pot and fill with 8 cups of water. Bring, uncovered, to a boil. Once the water comes to a rolling boil, add the lid and remove from heat. Let sit for an hour.
Regardless of what method you used, drain and rinse the beans.
Return the beans to the pot and cover with another 6 cups of water. Bring to a boil and then reduce heat to a simmer.
Simmer until tender. This can be as little as 30 minutes for pre-soaked white beans. Although quick soaked beans and chickpeas are going to take about 1½-2 hours to soften. You may need to adjust the temperature to keep them from boiling as they cook down.They should still keep their shape and not turn to mush. But theoretically putting a fork in them would split them in half.
Drain the chickpeas immediately after cooking and let cool to the touch.
Roast Opo Squash
This is optional. Opo squash is perfectly edible raw. Just peel the skin and scoop out the large inner seeds. You can easily substitute eggplant or other summer squash here. Roasting it will give an additional depth of flavor. But it is entirely optional.
Preheat oven to 350 degrees Fahrenheit.
Peel the opo squash, cut the stem off, and wrap in aluminum foil.
Cook for 45-60 minutes, or until the squash is tender. Let cool or refrigerate until cool to the touch.
Drain the chickpeas immediately after cooking.If you do chickpeas, rather than white beans, rinse and remove the skins. This is optional, but I recommend it specifically for baba ghanoush or hummus because it will result a smoother texture. This is less important for softer beans, though, which are more prone to breaking down.
Baba Ghanoush
Add all of the ingredients to a high-powered blender or food processor. Blend until mixture forms a smooth paste and you can no longer see pieces of chickpeas.
Once a smooth, consistent texture has been achieved, remove and chill before serving.I usually chill for about an hour. Although it entirely depends on how cool the ingredients were going into the food processor and whether blending warmed up the mixture.
For more information on hummus, I have an article on The Fundamentals of Making Hummus. This includes the chickpea versus garbanzo bean debate, canned versus dried chickpeas, and types of food processors and puréeing that work best (and least best).