Learn English – A better word for trying/ doing something you are not good at yet

Your original sentence is unclear to this extent: Do you mean that each spice should be put in separately (one spice at a time) or that they should all be mixed together into something like a curry powder and then added in equal fractional parts?

I'll assume the former (it's more rational for cooking for a couple of reasons).

You can say it this way:

Rather than adding all (of) the spices at the same time while cooking something, put them in one at a time at regular intervals, for example, every 2 minutes.

You can also say:

... put them in (separately) step by step, ..."

There's no need to clutter the sentence with unnecessary terms like "rounds" and "steps".

One way to say this is to use the word skill, or the expression more skilled, much like you did in your question:

Jeff always beats me in golf. He is far more skilled than I am.

Playing checkers with my 9-year-old can be boring. She just doesn't have enough skill yet to play competitively yet.

The Oakdale high school team couldn't compete against the Olympic volleyball team; the skill level of their opponents would simply be way too high.

Macmillan defines the word skill as:

the ability to do something well, usually as a result of experience and training

You can also convey this sentiment with the expression can't compete:

I couldn't compete against against Brianna Stewart. She's about 6 inches taller than I am, and one of the best athletes in college sports.

My son tries to play chess with me, but he just can't compete.

We could play darts for money if you wanted to, but, I'm telling you, you won't be able to compete. I used to play in weekly tournaments for about ten years.

We finally had to close down our burger restaurant. We just couldn't compete against the McDonald's across the street.

When compete is negated in the sentence, it often implies a gross mismatch like the one you describe in your question.