A bust for 2... f6?

The opening 1. e4 e5 2. Nf3 f6? is often played by very early beginners. It doesn't look good but it can be hard for a biginners to fully refute. For example, in this game (before I figured out the refutation) I had to play a positional struggle and then my opponent made a tactical error when running his king. This was a comfortable position for me but it was still not a simple execution in the opening. On to the first game!