Mercimek yemeği sıcak olunca daha lezzetli oluyor.

Because mercimek yemeği is a noun phrase meaning lentil dish / lentil meal / lentil stew, not the verb to eat lentils.

Here, yemek is being used as a noun meaning food / dish / meal. In this structure:

• mercimek = lentil
• yemek = food, dish, meal

But Turkish often forms this kind of compound with a suffix on the second noun:

• mercimek yemeği = lentil dish

The -i at the end of yemeği is part of that compound structure, not a separate object ending here.

So:

• mercimek yemek = to eat lentils
• mercimek yemeği = lentil dish

This is because mercimek yemeği is an indefinite noun compound in Turkish.

A very common pattern is:

• first noun + second noun + 3rd person possessive suffix

Examples:

• elma suyu = apple juice
• sebze çorbası = vegetable soup
• mercimek yemeği = lentil dish

So the second word often takes a suffix like:

• -ı
• -i
• -u
• -ü

depending on vowel harmony.

Here:

• base word: yemek
• in the compound: yemeği

The final k changes to ğ because Turkish often softens k when a vowel-initial suffix is added.

So the structure is:

• yemek → yemeği

Because mercimek yemeği is a normal compound meaning lentil dish, not the lentil’s dish.

Compare these:

• mercimek yemeği = lentil dish
• mercimeğin yemeği = the dish of the lentil / lentil’s dish

The second version sounds unnatural in ordinary usage because it suggests actual possession.

In Turkish, food names and many set combinations usually use the simpler compound pattern:

• tavuk çorbası = chicken soup
• domates salatası = tomato salad
• mercimek yemeği = lentil dish

So mercimek stays bare.

-ınca / -ince / -unca / -ünce usually means when, once, or whenever.

So:

• olmak = to be, become, happen
• olunca = when it is / when it becomes / once it becomes

In this sentence:

• sıcak olunca = when it is hot / when it gets hot

A natural English translation may depend on context, but the basic idea is that the next thing happens under that condition.

It can suggest either one, depending on context.

Literally, olmak often has the sense of become or be. With adjectives, Turkish frequently uses olmak where English might simply use be.

So:

• sıcak = hot
• sıcak olunca = when it is hot / when it becomes hot

In this sentence, the natural meaning is probably:

• when lentil stew is hot, it tastes better or
• once it gets hot, it becomes more delicious

Both are reasonable.

Good question. Turkish has more than one way to say when it is hot.

This sentence uses:

• sıcak olunca = when it is hot / when it becomes hot

Another possible form is:

• sıcakken = when it is hot

The version with olunca is very common and natural. It can sound a bit more dynamic, sometimes closer to once it gets hot.

So these are similar, though not always identical in nuance:

• Mercimek yemeği sıcak olunca daha lezzetli oluyor.
• Mercimek yemeği sıcakken daha lezzetli oluyor.

The first one may slightly emphasize the state being reached or the condition being met.

Because Turkish often uses olmak with adjectives to express becoming or ending up in a state.

Here:

• daha lezzetli = more delicious
• daha lezzetli oluyor = becomes more delicious / is more delicious

In English, we might simply say:

• it tastes better
• it is more delicious

But Turkish commonly says:

• lezzetli oluyor literally something like
• it becomes delicious / it turns out delicious

This is a very natural Turkish way of expressing how something tastes or seems under certain conditions.

Because they do two different jobs.

• sıcak olunca = subordinate clause, meaning when it is hot
• daha lezzetli oluyor = main clause, meaning it becomes/is more delicious

So the sentence structure is roughly:

• [When the lentil dish is hot], [it is more delicious].

Even though both come from olmak, they have different grammatical roles:

• olunca = when it is/becomes
• oluyor = it is becoming / it turns out / it is

Daha means more.

Turkish often leaves the comparison unstated when it is obvious from context. Here, the meaning is something like:

• It is more delicious when hot
  meaning
• It is more delicious than when it is not hot / than when it is cold

So the second thing being compared does not have to be said explicitly.

Examples:

• Daha iyi. = Better.
• Sıcakken daha güzel. = It’s nicer when hot.
• Mercimek yemeği sıcak olunca daha lezzetli oluyor. = Lentil stew is more delicious when hot.

In Turkish, -yor can be used not only for actions happening right now, but also for general tendencies, habitual situations, and what usually happens.

So:

• olur = becomes / is / would be
• oluyor = is becoming / tends to be / turns out to be

In everyday Turkish, -yor is very often used for general observations like this.

So daha lezzetli oluyor sounds very natural for:

• it tastes better
• it tends to be more delicious

Using olur might also be possible in some contexts, but oluyor sounds more conversational and common here.

It most naturally sounds like a general statement:

• Lentil stew tastes better when hot.

Turkish often uses a singular noun to talk about something in general, just like English can say:

• Coffee tastes better hot.
• Soup is nicer warm.

So mercimek yemeği here is probably not one specific dish on one specific occasion, but the food in general.

The sentence is:

• Mercimek yemeği sıcak olunca daha lezzetli oluyor.

A helpful breakdown is:

• Mercimek yemeği = lentil dish
• sıcak olunca = when it is hot
• daha lezzetli oluyor = becomes/is more delicious

So the structure is:

• Subject/topic + when-clause + main predicate

Turkish usually puts the main verb at the end, so this is very normal word order.

A rough literal arrangement would be:

• Lentil dish, when hot it-is/becomes, more delicious is-becoming

Natural English, of course, would be:

• Lentil stew is more delicious when it’s hot.

Yes, absolutely.

That is a very natural English translation, even if it is not word-for-word.

Turkish:

• Mercimek yemeği sıcak olunca daha lezzetli oluyor.

Natural English options:

• Lentil stew tastes better hot.
• Lentil stew is more delicious when it’s hot.
• Lentil stew tastes better when it’s hot.

The exact English wording may change, but the Turkish grammar stays the same.

The suffix here is a version of -ınca / -ince / -unca / -ünce.

Which form appears depends on the vowel in the previous syllable.

Since olmak contains o, the suffix becomes -unca:

• ol-unca

Other examples:

• gelince = when he/she comes
• bitince = when it finishes
• doğunca = when he/she is born
• görünce = when he/she sees

So olunca is just the vowel-harmony form that fits ol-.

Because Turkish often expresses states and changes of state with olmak, especially in everyday speech.

With adjectives, olmak can mean:

• to be
• to become
• to turn
• to end up

Examples:

• Hasta oldum. = I got sick.
• Hazır olunca söyle. = Tell me when it’s ready.
• Güzel oluyor. = It looks/turns out nice.
• Sıcak olunca daha iyi. = It’s better when hot.

So in this sentence, using olmak is very natural and idiomatic.