Would recommend the following 2 hawkers centers if you like a taste of local food yet not burning your wallet.

1) Old airport road hawker center. (Just take a MRT train and alight at Daokota station, 5 mins walk).
2) Chomp Chomp hawker center. (only fully open in the evening).

you may refer to this link: https://danielfooddiary.com/2019/05/07/chompchomp/