My sister grumbled to me about how the family is in extreme poverty while she cooked rice.
Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means cook and the verb vocab version is to cook or to boil. Often it has to do with cooking grains (to cook grains).
When you cook something, it's like you're attacking (たく) the food with boiling water or fire or whatever. Attack the food by cooking it!