In 5- to 5-1/2-quart slow cooker, layer onion, chicken, cauliflower and sweet peppers.
In medium-size bowl, whisk together the chicken broth, coconut milk, curry powder, salt, paprika, ginger and cayenne pepper. Pour over the chicken and vegetables in the slow cooker. Spread the chickpeas evenly over top.
Cover slow cooker; cook on high heat for 5 hours and 20 minutes.
At end of 5 hours of cooking time, soak rice noodles in warm water in a large bowl for 10 minutes. Drain.
At end of 5 hours and 20 minutes cooking time, add noodles to slow-cooker; cover and cook for another 10 minutes.
To serve, stir basil leaves into curry, if desired.