Maybe it's not as competitive as you think. Whatever the case may be, in this economic depression tell me who is buying cup cakes for $2.50 each? maybe in your little niche in Southern Cal where everyone is a millionaire.
I know personally the success of your idea. Yours truely has the contract to build the showroom cabinetry for The Cupcakery in Las Vegas.
The Cupcakeryâ„¢ which is long since compete and open for business. They now have 2 stores and will be franchising to Southern Cal this year or next depending on how many more millions of people continue to lose their jobs.
If you can strategically precisionly place this store in a shopping mall where people already do stop at specialty stores you have a good chance of success. Next to a grocery store you will lose. If you can strategically precisionly place your store in a heavy walking traffic main street with walkers and snack nibblers you have a good chance of success, like an "old town village" kinda place.
Further you can expand into offering a few fancy drinks like mocha and coffee. As long as you blow the doors off Starbucks prices you will win. What's wrong with charging just $2 for the same drink that Starbucks charges $5 for? It cost about 20 cents to make it. What you lose in single sale profit you will more then make up for in volume.
Good luck.................!