I have nested for each item j’s and it’s very slow.

It’s only 2 levels in but it’s too slow to be a viable product.

Am I likely overlooking something or can someone show me an example of a fast working nested item j?

My current project has 6 categories in the first list of item j

Then below that each of those categories has about 25 subcats.

It takes approx 3-4 seconds to get through the first category + first 25 subcats.

Multiplying by all 6 categories ends up taking around 20 seconds to do all 151 subcategories in total.

Here’s my stack