I guess it would depend. I have gone down the rabbit hole of Thai cooking whjich features many different curries from around the regions of the country. I have both made them and went store bought with canned curries actually made for the Thai market. Not all are “spicy”. The gtraditional ingredients will be chilis (of course), Kaffir Lime leaves, Galangol root, and of course Lemon grass. When I find them at the Asian Market I slice and dice and freeze them in individual servings for lagter use.
Yesterday I made some Chili Paste which is sort of a Chile Jam..spicy and sweet as you wish to make it...I made it spicy this time. Good Stuff
As for Singaporean recipes, they will be different but similar. Pandan leaves? Maybe for desserts, but in a Curry? Even I know that... Oh Well, its the NYT.
Lemongrass is easy to grow. Stick some in a pot, water well, and in one summer you have a nice big clump. Pretty plant, too. You have to bring it in before frost, of course.
Same with galangal root (also known as “buffalo grass” in SE Asia). Put a rhizome in a pot, not too deep — just about an inch — in well-drained soil (add sand or vermiculite). After it sprouts its grassy blades and gets happy, the rhizome starts spreading and you can harvest. Same deal with needing to bring in before frost.