Here’s your battle plan. Step one: rinse one cup dry beans. Check for tiny pebbles—they break teeth. Step two: boil them in four cups of water with that pinch of baking soda.
Step three: cook at a roaring boil for 10 minutes. Then drop the heat to a low simmer. Cover and cook for 45 minutes. Check at 30 minutes—taste one. If it’s soft, you win.
Still hard? Add more water and simmer another 15 minutes. Don’t add salt yet—salt can firm them up. Salt after they are perfectly tender. It’s a weird science, but it works.