That, plus a great deal of planning.
The self-proclaimed chocoholic, who has a background in marketing and retail, wanted to create a chocolate boutique featuring confections from around the world.
That meant doing a lot of research -- and taste testing-- to make sure everything in her shop is something her customers would want to indulge in.
It also means working with small artisan chocolatiers as they tend to create "some of the most beautiful chocolates made of only the finest ingredients," she said.
While Castle Hill carries a staple of tried and true crowd-pleasing chocolates, Sullivan likes to expand her customer's tastebuds and offer them something "completely new and unexpected."
Keeping it local is another mission.
"We want to offer customers something uniquely made in Newtown," she said.
Case in point: Chocolate covered fresh blueberries, which are hand-dipped in the shop's in-house commercial kitchen.
"They are addictive, to say the least," she said.
Though her shop is only a year old -- it opened in May 2016 -- the Newtown resident said she spent a lot of time on the development of the business, from how to present it, to naming it and of course, choosing the right mix of products.
"Deciding on which chocolate to include in our collection, as you may guess, was the fun part," she said.
New for the store: kids birthday parties for those five and up. Details are on the website but in essence, expect a chocolate pizza themed in-store birthday celebration.Castle Hill Chocolate is at 6 Queen St., (203) 270-1199, www.castlehillchocolate.com/.
Click here to follow Daily Voice Brookfield and receive free news updates.