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Cooking takes way too much time.
Literal
Cooking [for-に] too-much time [subject-が] takes-too-much.
Double emphasis on excess: あまりに (too much) stacked with ~すぎる (to be excessive). 時間がかかる is a set expression meaning 'to take time,' where が marks 時間 as the subject of かかる. Stacking あまりに and すぎる intensifies the frustration — each alone would suffice, but together they underscore the complaint.