Technically speaking, you don't need fresh pineapple to make an easy pina colada.  What I like to do is cut a fresh pineapple, then freeze it, then blend it.  Tips: I recommend using frozen chunks of pineapple so you don't need to use as much ice. However, that doesn't mean that you technically have to start with a fresh pineapple. You can start with a bag of frozen pineapple tidbits or chunks. If fresh pineapple is in season there's nothing better. So sweet and perfect! But freeze it first. Otherwise just use bagged frozen pineapple from the get-go. Trader Joe's Pineapple Tidbits work great if you have a TJ's in your area. I do not recommend using canned pineapple that you freeze then use. Something about the taste just doesn't work for me although everyone is different.