I once mixed vanilla and chocolate ice cream. I got Chanilla!
It was delicious, you both should try it.
The meaning of the parable is that chocolate has much to offer, as does vanilla. To stick to one, means you will never know the delight of the other.
In other words, a dog or a cat or both, can be delightful pals and companions. If you only want a pet rather than a true friend, get a goldfish.