Hi there, Laura!
Thanks for stopping by the Disney Parks Moms Panel with your question!
I am elated to hEAR you are planning on starting your magical morning at 
Be Our Guest Restaurant. The 
breakfast there is delicious! To dine in Beast's enchanted castle is truly a special experience. My favorite room there is the grand ballroom where Belle and Beast danced. If you look closely at the windows, you can see the falling snow!
The 
Disney Dining Plans add value, flexibility, and convenience to our Walt Disney World Resort vacations and I' glad you have opted for the Disney 
Quick-Service Dining Plan! Usually when it comes to souvenir items like souvenir cups or popcorn buckets, these items are considered to be merchandise and are not included in the Disney Dining Plans. I have paid out of pocket for a souvenir cup from Be Our Guest Restaurant and I absolutely love it! You can always ask once you arrive at the location; perhaps a Cast Member can explain other options! 
You can see a list of details of snack items 
here. It is down the page a bit; look for "Snacks" for the list of items. Also, included in the price of your Disney Dining Plan is your Resort Refillable Mug! These make for wonderful souvenir cups, and I use mine almost daily while I'm home. It brings a little bit of magic to my day! 
Laura, I hope you have the most enchanting vacation at 
Walt Disney World Resort!
Aena