Saying "least favorite" the other way

Dear respectable audience

I am not a native English speaker, though with some amount of experience and proficiency in its use.

Here is what I would like to ask:

does the following sound natural or not for native English speakers?

Spinach is a vegetable I don't like the most

in a sense of

Spinach is my least favorable vegetable

As you already said:

Spinach is my least favourite vegetable.

There's nothing wrong with that and it's perfectly understandable.

On the other hand:

Spinach is the vegetable I don't like the most.

Even though this is understandable, it does not sound natural simply because nobody uses that phrasing.

A more natural version would be:

Spinach is the vegetable I dislike the most.

In this particular sentence construction, dislike is preferable to don't like. (Although don't like can be used in other constructions without a problem.)

The reason behind this is that when we use a comparative term, it's in conjunction with a single word rather than with a word and its negation.

These sound natural:

The most likely.
The greatest strength.
The least weak.

These alternate versions sound strange:

The least not unlikely.
The greatest not weakness.
The least not strong.