chijeureul manhi neoheossdeoni beoteo masi jal an neukkyeojyeosseo.

Korean often leaves out the subject when it is obvious from context.

In 치즈를 많이 넣었더니, the speaker is understood to be the person who added the cheese, so English would naturally supply I even though Korean does not say it explicitly.

This is very normal in Korean:

• 치즈를 많이 넣었어 = I added a lot of cheese
• literally, though, it just says added a lot of cheese

-었더니 often means something like:

• after I did X, I found that Y happened
• I did X, and as a result Y happened
• when I did X, it turned out that Y

So 치즈를 많이 넣었더니 버터 맛이 잘 안 느껴졌어 has the sense of:

• the speaker added a lot of cheese,
• and then noticed the result that the butter flavor did not come through well.

Compared with a plain because, -었더니 often sounds a little more like the speaker is looking back on what happened and reporting the outcome they experienced.

많이 modifies 넣었더니.

So it means:

• I added a lot of cheese

It does not mean the speaker tasted a lot or that the butter flavor was strongly felt. It specifically describes the amount of cheese that was added.

They have different grammatical roles.

• 치즈를: cheese is the object of 넣다 (to put in / add)
• 버터 맛이: butter flavor is the thing that is or is not perceived

That second part is important. Korean often says that a taste, smell, or feeling is felt rather than saying I felt it.

So:

• 치즈를 넣다 = to add cheese
• 버터 맛이 느껴지다 = the butter flavor is noticeable / can be tasted

That is why 버터 맛이 takes the subject marker 이.

맛 means taste or flavor.

So 버터 맛 literally means butter taste, but in more natural English it is usually:

• butter flavor
• the taste of butter

This kind of noun combination is very common in Korean:

• 딸기 맛 = strawberry flavor
• 초콜릿 맛 = chocolate flavor
• 커피 맛 = coffee flavor

So 버터 맛 is completely natural Korean.

The two are related, but the nuance is a little different:

• 느끼다 = to feel / sense / notice
• 느껴지다 = to be felt / to come across / to be noticeable

In food descriptions, 느껴지다 is very common because Korean often treats taste or aroma as something that comes through or is perceived.

So:

• 버터 맛을 느꼈어 = I felt/noticed the butter flavor
• 버터 맛이 느껴졌어 = the butter flavor came through / was noticeable

The sentence uses 느껴졌어 because it focuses on how noticeable the butter flavor was, rather than directly emphasizing the speaker as the one doing the noticing.

In Korean, 잘 안 + verb often means:

• not very well
• doesn’t easily
• not clearly

So 잘 안 느껴졌어 means:

• it didn’t come through very well
• it wasn’t very noticeable
• I couldn’t really taste it clearly

Here, 잘 does not mean well in a positive sense. In this pattern, it helps create the meaning not well or not clearly.

Compare:

• 잘 보여 = I can see it well
• 잘 안 보여 = I can’t see it well / it’s hard to see

The same idea applies here with 느껴지다.

Yes, you could, and it would be understandable.

But there is a small nuance difference:

• 버터 맛이 잘 안 느껴졌어 = the butter flavor didn’t come through well
• 버터 맛을 잘 안 느꼈어 = I didn’t really notice the butter flavor well

The original sentence sounds a bit more natural for describing the food itself and how its flavor profile came across. The alternative version sounds a bit more centered on the speaker’s experience.

So both are possible, but 느껴지다 fits this kind of food comment especially well.

Because the sentence is not really saying it was completely impossible. It is saying the butter flavor didn’t come through clearly.

Compare:

• 버터 맛이 잘 안 느껴졌어 = the butter flavor wasn’t very noticeable
• 버터 맛을 못 느꼈어 = I couldn’t notice/taste the butter flavor

The version with 못 sounds a bit stronger and more absolute.
The version with 잘 안 sounds softer and more natural when you mean the flavor was weak, masked, or hard to pick up.

It is casual informal past tense.

The dictionary form is 느껴지다, and the polite version would be:

• 치즈를 많이 넣었더니 버터 맛이 잘 안 느껴졌어요.

So the original sentence is something you would say in casual conversation with a friend, family member, or someone you speak informally with.

Not exactly.

It can often be translated with so or because, but it usually has a slightly richer feeling:

• the speaker did something,
• and then discovered or observed the result.

So here it is not just a dry logical connection. It feels more like:

• I added a lot of cheese, and then it turned out that the butter flavor didn’t really come through.

That sense of result noticed afterward is a big part of why -었더니 is used here.