Place dry kidney beans in a bowl and cover with plenty of water.

Soak the beans for at least 8 hours or overnight.

Drain the soaked beans.

Transfer the drained beans to a large pot.

Cover the beans with plenty of fresh water.

Add salt to taste.

Add 1/4 teaspoon of cayenne pepper.

Bring the pot to a boil.

Reduce the heat to low and simmer until the beans are soft, approximately 90 minutes.

Drain the cooked beans and season with additional salt to taste.

In a food processor, grind the shelled walnuts and garlic cloves into a fine paste.

Add red wine vinegar, 1/3 cup of water, 1 tablespoon of chopped fresh parsley, and 1 tablespoon of chopped fresh cilantro to the food processor.

Add 1/4 teaspoon of cayenne pepper to the food processor.

Process all ingredients in the food processor until smooth.

In a large bowl, mix the cooked beans, minced white onion, chopped cooked chicken (optional), and the walnut-garlic dressing.

Cover the bowl and chill in the refrigerator for at least 1 hour before serving.

Garnish with 1 tablespoon of chopped fresh parsley and 2 tablespoons of chopped fresh cilantro before serving.