Microwave Tricks: Black Beans

Cooking seasonally is a tricky thing–especially if your season currently includes hurricanes or extreme heat. Pasadena has finally cooled down to 80s/90s with a bit of cloud cover, but last week’s 105-degree afternoons were a serious challenge. It was so bad the only time to go out for a walk was about 5:30 in the morning. Hard to think school has been in session for a month, it’s already September, and Rosh Hashanah is a week and a half away. Running the oven is, to put it bluntly, not an option, and the stove top isn’t much better in my small and easily overheated galley kitchen.

Microwaving is a powerful way to cut the time and pain (and airconditioning bills) for bulk cooking of things like vegetables, rice, pasta…and dried beans, which are much cheaper and more versatile (and much lower in sodium) than canned. Make a bean stew or chili and you can zap a portion of it at will later in the week. Plus bean salads can be served cold–a plus for weeks like the ones we’ve had recently.

But for microwaving, you usually have to adjust whatever method is spelled out in a recipe to your oven, your containers, your food quantities. Microwave times are sensitive to all of those factors, plus how much water you have (water’s the main molecule microwave radiation acts on) and whether or not you’ve got a lid.

Most people don’t try to make changes based on their first-run results and most cookbooks never really explain how to make useful adjustments. Predictably, most microwave cookbooks end up in the Last Chance bin at your local Friends of the Library booksale.

It’s a shame, because once you’ve got your timing and so on down, you can repeat it with reliable results.

Over the years I’ve posted basic heat-to-simmer-and-let-sit-to-absorb microwave methods for cooking split peas, chickpeas, lentils and other bulk dried beans. Lentils and split peas always did work out well without needing to soak them first–they tend to be easier to cook quickly by standard stovetop boiling too. Chickpeas work okay if you presoak them or hot-soak in the microwave (heat briefly in water just to cover, let stand 15 minutes or so and let them swell up) before the main cooking, and adding a dash of baking soda to the soak water really helps. Same with gigantes (giant favas)–which I’ve now decided cook better with the skins left on, same as if you were boiling them, and they’re certainly a lot quicker and easier to peel afterward–also more fun.

But some beans just seem to toughen if you don’t presoak overnight or if you microwave them too long. Black beans and kidney beans have given me more trouble than they seem to be worth–and I’m a bit reluctant to post this because it’s fussier than I like to admit even after adjusting the method successfully. Microwaving isn’t supposed to take more time and fuss than straight boiling on a stove, or working with a pressure cooker, if you have and trust yourself with one.

But this is a good illustration of how to use a microwave as a workaround when you don’t, and it shows you how you might think about making adjustments based on what the food is doing or not doing.

I microwave because I want something relatively safe, that doesn’t heat up the kitchen, and that turns itself off when done because, let’s face it, I’d rather be reading or writing than waiting for a pot of water to boil or jumping up at the whistle to avert an explosion. And I want the beans properly cooked and tender in less total microwave time at the least and without having to boil them afterward on the stove. I’ve done that before and I’ll probably do again if it ever cools down enough, but I’d rather not have to. The prior microwaving steps still shorten the stovetop time to maybe half an hour, but really, I’d rather it were all microwave, no fuss (I can dream, can’t I?)

So after a rethink of my previous methods, I’ve made some changes to the way I cook black beans from scratch by microwave. It also works for things like brown rice, steelcut oats, and other tough, uncut, unpeeled whole grains like farro or pearl barley when you’ve forgotten to put them up for soaking overnight, and at least for the rice it’s quicker than the 45 minutes or so of my previous brown rice method–maybe 20-30 minutes for a pound or two of brown rice. For the beans, maybe an hour of time total, with sitting and rechecking. Maybe less if your beans are fresh enough and/or you remembered to soak them overnight first.

Cracking the method

It starts with the water. I had been covering a pound of dried beans (or brown rice) with more than an inch of water and heating it all, or else heating that much water by itself (more than a quart) and then tipping in the rinsed beans to soak for a bit. But since the water molecules are what the microwave heats up first for preference, the more water you have, the longer it takes for the temperature to rise–all those molecules are dividing up the energy amongst themselves, so each one gets less. Heating up 1-2 quarts of water to a bare simmer can take 7-8 minutes on high power in my microwave. Puts a strain on the microwave magnetron.

The black beans seem to need an actual near-boil to get going. So using less water to heat it hotter faster seems like the right way to go. On the other hand, too little water and you not only risk scorching the beans but you also don’t have enough water for the beans to absorb.

So I decided to split the difference and put in just enough water to cover–with a lid–and then heat to a boil  and let it absorb a few minutes with the power off. That kind of half-steams, half-simmers the beans–kind of like pressure cooking, but less dangerous. After absorption, I top up with a little more water just to cover and reheat once or twice. Since the beans and most of the liquid are still pretty hot, getting back to a near-boil with the added water should only take a few minutes.

I generally use a 2.5 quart rectangular snaplock container (my handy Kroger store-brand-style cheapos) and a pound of dried, rinsed black beans.  If you’re doing twice as much it will take you longer. Soaking the beans cold overnight beforehand would obviously be the smart way to go if you do. Or if you live in a cooler zone and don’t mind a big boiling soup kettle or a slow cooker, and can remember to soak your beans overnight first and keep the water topped up in the pot, that might be your better bet for a serious chili fest for a cast of thousands. But a pound of beans is about 10 servings’ worth, so it’s enough to be “bulk” in my world.

Black Beans by Microwave

1. Put the beans in the container and then fill up with water just to cover by about 1/4 inch or a little more, stick a lid on and microwave just to where the liquid starts to bubble up toward the lid–about 5 1/2 minutes in my microwave. Let them sit a few minutes with the lid on and the power off to absorb the hot water. The beans should swell up just above the waterline and the skins will look a little loosened and puckered on the top layer.
2. Stir up with a spoon–the bottom of a big container usually gets less of the microwave energy than the top, and the beans on the bottom may not have soaked up as much. Add another bit of water just to cover the new bean level by 1/4-1/2 inch.
3. Stick the lid back on, let sit a few minutes to absorb more, add a dash of baking soda, stir and microwave another 2-3 minutes. Since the majority is already hot, you want to reheat just to the boil-up point without it actually boiling over and making a hot mess on the turntable. If it doesn’t start seething up, hit it up for another minute at a time until it does and keep an eye on it (sorry, I know–but it beats not getting it hot enough or having to clean up after the fact). Once you have your times down, you can just do it without babysitting so much, so you might want to make a note of how long it takes.
4. Let the container sit with the lid on 10-15 minutes, or longer if you feel like it, and check again by sampling one or two of the smaller beans for doneness. Add a little more water, stir, another 3-4 minutes of microwaving, just until it seethes upward toward the lid. You might need to do it another round.

When are they done? When they don’t smell raw anymore. When the liquid has turned from the initial black thin liquid to brown and syrupy. When you stir the beans around, stick the spoon in and sample one or two of the smaller beans and they’re tender–the smaller ones are a better test than the big ones, which have obviously soaked up successfully.

What if they’re just not going past about 2/3 of the tenderness you want? Try doing the steaming/pressure step again with fresh water, because the thick brown stuff may be inhibiting further absorption at that point (osmosis, ya know). Pour off the thick black/brown liquid with the baking soda in it, rinse once and fill the container up with fresh water just to the level of the still-hot beans, put the lid on and nuke 3-4 minutes or until it seethes upward.  Let it sit 5-10 minutes and recheck, maybe give it another 2 minutes on high once it’s basically tender–it seems to work decently.

Then use them! Or cool and then freeze them (or half of them) in a snaplock container with some liquid for later–when you rethaw them, they should tenderize further.

Microwave Black Bean Chili

This is not the Texan Chili Cookoff for the Prize Money and Bragging Rights style of chili. It’s the easy 10-15 minute college dorm or camping trip style of thing (only in a microwave) and surprisingly useful to be able to throw together for cheap weeknight eats when everyone’s heading off in a different direction. If you have a small household, it makes handy leftovers.

• 2-3 cups cooked black beans
• medium to large tomato and about half an onion, chopped
• bell pepper (any color) or jalapeno or both, chopped, optional
• spoonful of olive oil, optional
• half a cup or so of chipotle or other salsa you like. My preference is Trader Joe’s no-salt-added chipotle/roasted tomato salsa.
• clove of garlic, mashed/minced/grated
• squeeze of lime juice and/or couple of tablespoons of vinegar
• cumin, coriander, cilantro, chili powder and/or hot pepper flakes to taste

1. Wilt the tomato, onion and bell or hot pepper chunks in the microwave by putting them in a big lidded container with the optional spoonful of oil and stirring, putting on the lid and microwaving on high 3-5 minutes or until wilted and the onion’s no longer smelling raw.
2. Pour in the beans and other ingredients, a small amount of water if it looks dry, stir, put the lid on, microwave to heat through 5-6 minutes. Let sit and then taste–correct spices and acidity before deciding whether to add any salt.