Normal food is just as effective as "sports nutrition" for fuelling your commute.
Pick something with slow energy release (low GI) like banana, malt loaf, fig rolls, sandwich, pie.
Avoid the sugar rush of high GI foods, mars bars, twix, wagon wheels, battenburg cake.
Make sure you drink enough before you leave to start well hydrated. A nice mug of tea works as well as a shot of Brawndo (The Thirst Mutilator), both have electrolytes.
Pre-fuel in advance of your ride so you are fully fuelled when you start.