Like payouts from pillar-3a products, capital withdrawals from pension funds are taxed once only at a special rate. So, in order to minimize your tax burden, you should avoid making two withdrawals of this kind in the same year. You can calculate the one-off capital tax here.
The funds you withdraw are later taxed as assets and the interest paid on the invested funds as income. Asset depletion itself is tax-free, however.
If you draw a pension from your pension fund, on the other hand, you must pay income tax on it. The upside: the pension is paid out for as long as you live.