This comforting side dish is perfect on chilly evenings.
Place the beans in a large bowl, and cover with cold water. Soak overnight; drain.
Place the beans in a medium saucepan, and cover with cold water. Simmer over medium-low heat, covered, until tender but not mushy, 45 to 60 minutes. Drain beans in a colander, reserving 1 cup cooking liquid.
Heat the oil in a medium saute pan set over medium heat. Add the onion, cover, and cook until translucent, about 7 minutes. Add the garlic, and cook until fragrant but not brown, 1 to 2 minutes more. Add the beans, the reserved cup cooking liquid, and 1 cup chicken stock. Continue simmering, covered, until the beans are very tender, about 25 minutes.
Stir in sage, and season with salt and pepper. If mixture is dry, add up to 1/2 cup remaining chicken stock. Serve hot.
In step 2, it is better to slightly undercook the beans than to overcook them since they will continue cooking as the stew simmers.