、。
Dinner's ready, so you can eat whenever you want.
Literal
Dinner-of preparation [topic-は] done-[ongoing-ている]-because, anytime eat-want-time-[at-に] be-able-to-eat-[sentence-final-よ].
A warm, hospitable sentence packed with small grammar. いつでも ('anytime, whenever') built from the interrogative いつ + particle でも ('even, any'). 食べたいとき ('the time when you want to eat') is a nominalized relative clause. 食べられる is the potential form of 食べる — 'can eat.' The から here marks cause ('because preparation is done, [therefore] you can eat').