Heat the oil in a large pot or deep skillet over medium heat.
Add the sliced smoked sausage and cook, stirring occasionally, until browned on both sides, about 5–7 minutes.
Stir in the diced onion and cook until the onion is softened and lightly golden, about 5 minutes.
Add the drained and rinsed red kidney beans and the chicken broth to the pot. Stir to combine, scraping up any browned bits from the bottom of the pan.
Bring the mixture to a gentle boil, then reduce the heat to low and let it simmer uncovered for 20–25 minutes, stirring occasionally, until the beans are creamy and the liquid has thickened slightly. If it gets too thick, splash in a bit more broth or water.
Taste and adjust seasoning with salt and pepper if desired (optional, not counted as an ingredient).
To serve, spoon cooked white rice into bowls and ladle the red beans and sausage mixture over the top. Stir together in the bowl if you like a creamier texture.
For meal prep, let the beans and rice cool completely, then portion into airtight containers. Store in the fridge for up to 4 days and reheat in the microwave or on the stovetop with a splash of water or broth.
To keep this at six ingredients, the base recipe is intentionally simple, but you can easily dress it up when you have a few extra minutes or pantry staples. For more classic New Orleans flavor, add chopped celery and green bell pepper along with the onion to make a quick “holy trinity” base. A teaspoon or two of Cajun or Creole seasoning, smoked paprika, or a bay leaf will deepen the flavor without much effort. If you prefer a creamier texture, use the back of a spoon to mash some of the beans against the side of the pot during the last 10 minutes of simmering. For a lighter version, swap the smoked sausage for turkey sausage or use a fully cooked chicken sausage. To make it vegetarian, skip the sausage and use vegetable broth instead of chicken broth; a dash of liquid smoke or smoked paprika will help replace that smoky flavor. You can also change up the beans—red beans, small red beans, or even pinto beans all work in a pinch. For busy weeks, cook a big batch of rice on Sunday and keep it in the fridge so this recipe becomes a true 20–25 minute weeknight dinner.