Heat a small pan over medium-low heat. Add the roughly chopped walnuts to the pan, and toast until fragrant/lightly golden. Keep a close eye on them and occasionally toss them around with a spoon. This should take between 5-7 minutes and may seem slow at first, but once they start to toast, they toast quickly. So it's important to watch them so they don't burn. Once nicely toasted, remove from heat and set aside.