Cliff/shed radical (Kangxi 27) wrapping the upper-left — depicts an overhanging roof or rock-shelter. Marks 厨 as a sheltered space. Other shed-roof characters: 原 plain, 厅 hall, 历 calendar, 厌 detest. The kitchen is the sheltered cooking area of the home.
Inside the shed on the left — historically a stemmed sacrificial vessel pictogram, later borrowed for 'bean'. Provides part of the phonetic chú (via the older sound family of 厨 ≈ dòu/chú). Faintly semantic too: a vessel inside the shed evokes cooking pots in a kitchen.
Hand/inch element on the right — depicts a hand measuring at the wrist pulse. In 厨 the 寸 is the working hand of the cook, preparing food beside the 豆 vessel under the 厂 shed. Together: shed + vessel + working hand = kitchen.