Если котлеты долго тушить в соусе, они становятся мягче и вкуснее.

In this sentence, the infinitive тушить is used in a general, impersonal condition:

Если котлеты долго тушить в соусе...
= If you simmer cutlets in sauce for a long time...
= If cutlets are simmered in sauce for a long time...

Russian often uses the infinitive this way when the subject is not specific. The idea is not about one particular person doing the cooking, but about what happens in general.

You could also say:

Если долго тушить котлеты в соусе, они становятся мягче и вкуснее.

That may feel a little easier to understand, because the object comes after the infinitive.

Here котлеты is accusative plural, because it is the direct object of тушить:

тушить что? → котлеты

The reason this can be confusing is that for inanimate plural nouns, the accusative form is the same as the nominative form.

So:

• nominative: котлеты
• accusative: котлеты

They look identical, but in this sentence the function is accusative.

In cooking, тушить means something like:

• to stew
• to braise
• to simmer slowly

It usually implies cooking food for some time with liquid, often on low heat.

So тушить в соусе means to cook/simmer in sauce.

Be careful: тушить has other meanings in other contexts, such as to extinguish:

• тушить огонь = to put out a fire
• тушить свет = to turn off the light (colloquial)

So the exact meaning depends on context.

Because this sentence describes location or environment, not motion.

• в соусе = in the sauce / while in sauce
• в соус would suggest movement into the sauce

Here the cutlets are being cooked in sauce, so Russian uses в + prepositional case:

• соус → в соусе

This is the normal pattern for something happening inside a place, substance, or medium.

Russian often uses the present tense in sentences that express general truths, recipes, instructions, or regular results.

So:

Если котлеты долго тушить в соусе, они становятся мягче и вкуснее.

means:

• If you simmer cutlets in sauce for a long time, they become softer and tastier.
• or in more natural English: ...they will become softer and tastier.

English often uses will in this kind of conditional translation, but Russian does not need a future form here. The present tense is enough to express a general result.

Становиться means to become.

So:

• они становятся мягче = they become softer
• они становятся вкуснее = they become tastier

This verb is very common when something changes state or quality.

Compare:

• Они мягкие. = They are soft.
• Они становятся мягче. = They are becoming / become softer.

So the sentence emphasizes a change caused by slow cooking in sauce.

Because мягче and вкуснее are the comparative forms:

• мягкий → мягче = softer
• вкусный → вкуснее = tastier

The sentence is saying that after this cooking process, the cutlets become softer than before and tastier than before.

If you said:

они становятся мягкими и вкусными

that would mean:

they become soft and tasty

That is also grammatically correct, but the original sentence uses the comparative to emphasize improvement.

After становиться, Russian often uses:

1. a noun/adjective in the instrumental case
   
   • становятся мягкими и вкусными

or

2. a comparative form
   
   • становятся мягче и вкуснее

Comparatives like мягче and вкуснее do not take instrumental endings here. They stay in their normal comparative form.

So both are possible, but they mean slightly different things:

• становятся мягкими и вкусными = become soft and tasty
• становятся мягче и вкуснее = become softer and tastier

The original focuses on a change relative to an earlier state.

Они refers back to котлеты and serves as the subject of становятся.

It helps make the sentence clear:

Если котлеты долго тушить в соусе, они становятся мягче и вкуснее.

Without они, the sentence would sound less natural and less clear in standard written Russian, because:

• in the first clause, котлеты is the object of тушить
• in the second clause, we need a clear subject for становятся

So они neatly signals: the cutlets become softer and tastier.

Yes. Russian word order is flexible, and you could also say:

Если долго тушить котлеты в соусе, они становятся мягче и вкуснее.

This version may be a bit easier for learners, because the infinitive comes before its object in a more expected order.

The original sentence is still perfectly natural. Russian often moves words around for rhythm, emphasis, or style.

Тушить is the imperfective verb, and it is the natural choice here because the sentence talks about:

• a process
• duration (долго = for a long time)
• a general repeated truth

Imperfective is typically used for ongoing or process-based actions.

A perfective verb such as потушить would sound less natural here, because the focus is not on one completed action, but on the cooking method and its result in general.

So долго тушить = to simmer/stew for a long time is exactly the kind of situation where imperfective is expected.

Not always exactly.

In Russian, котлета / котлеты often refers to a minced-meat patty, something closer in many cases to:

• a meat patty
• a croquette-like cutlet
• a Russian-style minced cutlet

It does not always mean the same kind of cutlet an English speaker may imagine.

So if you translate it as cutlets, that is often acceptable, but culturally the food may not be identical.

Because Если котлеты долго тушить в соусе is a subordinate clause introduced by если (if), and Russian normally separates it from the main clause with a comma:

Если ..., они становятся ...

This is standard Russian punctuation.

So the comma marks the boundary between:

• the condition: Если котлеты долго тушить в соусе
• the result: они становятся мягче и вкуснее