Ok I'll give you two things . 1. Make atleast 10 phone calls during the week to restaurants and ask at what time do they close , and be sure to mention the word 'restaurant' since its your feared word. I would ask you to do more since only that way you can reduce your fear on that word but I feel if you have trouble speaking on the phone itself then this would be a good starting point . 2. Notice your speech throughout the week when you are talking with your parents. And notice what's the reason why you're stuttering . It may be that you're just trying too hard to hide your stutter. This is not really a challenge but it will be helpful nonetheless