Is there any food that you don’t like to eat?
Suppose it’s Natto.
One of your best friends brought you a pack of Natto.
Now you have to eat it, at least, you need to try, otherwise, not eating can be impolite.
You take a bite, then you find it is actually delicious without your expectation!!!
Your friend asks you “どう？”(How is it?)
You say “食べたら、おいしかった”.
Here, you FOUND Natto is delicious.
Let’s take a look more examples.
When you arrive at the station, you found the station was crowded.
When you drink a soup, you found it was really hot.
When you buy clothe, you found some dirt was on it.
When you study Japanese, you found it easier than you thought.
You got it?
This is one of the uses of 「たら」.