This is the step that turns a till into a business tool. Without recipes a POS can tell you that you sold 120 karaks; with recipes it can tell you what those karaks cost you in tea, milk, sugar, gas and cups, and what you actually made.
It also fixes stock counting. When a recipe exists, selling a burger deducts one bun, one patty and a portion of sauce automatically, so ingredient levels stay right without anyone counting by hand.
Two things make recipe costing worth the setup effort: it exposes items priced below what they cost once waste and portions are counted, and it produces a 'can make' figure — how many of a dish you can still produce with the stock on hand.
Start with your ten bestsellers rather than the whole menu. That covers most of your revenue, takes an afternoon, and is usually enough to find at least one item priced wrong.