hey presto 
exclamation British
A phrase announcing the successful completion of a trick, or to suggest that something has been done so easily that it seems to be magic: press the start button and, hey presto, a copy comes out the other end...
- You type in the message, press a few buttons, and hey presto!
- My car even has ‘climate control’, which means that you set the temperature that you'd like, then press ‘auto’ and hey presto!
- Take one disco drumbeat, add a bouncy bassline, throw in a grouchy guitar noise and a cheeky mockney songsmith, and hey presto!