Toradora!: Bentou no Gokui

とらドラ！ 弁当の極意

Synopsis:
An unaired episode included in the Blu-ray box set.

Yuusaku brings an extravagant bento box to share with the class, which makes Ryuuji feel inferior about his own bento making skills. Desperate to beat his bentos, Ryuuji obsessively tries to compete against them to the point where he even brings a rice cooker to school. After Taiga brings him some salty onigiri, Ryuuji realises that the true meaning of bentos is not the taste, but the feelings that are put into it.

(Source: Wikipedia)