The Golden Churros are a special item to help celebrate the 50th Anniversary of Pirates of the Caribbean. You can get them at the cart over by the Rivers of America between Pirates and Haunted Mansion. You can specify regular (cinnamon and sugar) churro or the golden (sparkly lemon flavored) churro when you order. The cart has two different pans with the sugar topping that the churro maker can use.
I wasn't sure about a lemon flavored churro, but it was surprisingly good! I still prefer the traditional, but if they keep the golden churros around I will probably get one again.
There is a thread (probably on the 2nd to 4th page) with information on updates over the last few years. I'll see if I can find it for you.