Если бы у нас не осталось плова, я бы быстро приготовил котлеты из говядины.

Бы is the particle that helps form the conditional mood in Russian, similar to would in English.

In this sentence:

• Если бы у нас не осталось плова = If we had no pilaf left
• я бы быстро приготовил котлеты из говядины = I would quickly make beef cutlets

Russian often uses бы in both parts of this kind of unreal/hypothetical sentence:

• in the if-clause
• and in the main clause

That is very normal.

Compare:

• Если бы он пришёл, я бы поговорил с ним.
• If he came / had come, I would talk / have talked with him.

In English, would usually does not appear in the if-clause, but in Russian бы often does.

Если by itself usually introduces a real or possible condition:

• Если у нас не останется плова, я приготовлю котлеты.
• If we have no pilaf left, I will make cutlets.

This sounds like a real future possibility.

Если бы introduces an unreal, imagined, or hypothetical condition:

• Если бы у нас не осталось плова, я бы приготовил котлеты.
• If we had no pilaf left, I would make cutlets.

So:

• если = if
• если бы = if ... were / had / would in a hypothetical sense

Because these mean different things.

• у нас не осталось плова means we have no pilaf left / there wasn’t any pilaf left with us
• мы не оставили плов means we did not leave the pilaf or we didn’t leave any pilaf behind

The sentence uses the common Russian possession/existence pattern:

• у нас = with us / in our possession / at our place

So у нас не осталось плова is a natural way to express that the pilaf was gone or used up.

This is very common in Russian:

• У меня нет времени. = I don’t have time.
• У нас осталось мало хлеба. = We have little bread left.
• У них не осталось денег. = They had no money left.

Because after не осталось Russian normally uses the genitive case for the thing that is absent or left in some quantity.

So:

• плов = nominative
• плова = genitive

This is especially common with:

• negation
• quantities
• absence/existence expressions

Examples:

• осталось хлеба = there was some bread left
• не осталось супа = there was no soup left
• мало времени = little time
• нет молока = there is no milk

Since pilaf is treated as an amount of food rather than a clearly counted object, the genitive is natural here: не осталось плова.

This is a very common thing that confuses learners.

In не осталось плова, the verb is used in an impersonal/existential construction. Russian often uses neuter singular past tense in this kind of sentence:

• осталось
• не осталось
• было
• не было

So the sentence is not working like a simple subject-verb structure where плов is a normal nominative subject.

Compare:

• Плов остался. = The pilaf remained.
  Here плов is the subject, so the verb would be masculine singular: остался.

But:

• У нас не осталось плова. = We had no pilaf left.
  This is an existential/amount construction, so Russian uses осталось.

You can think of it as something like there remained no pilaf.

Because приготовил is perfective, and here Russian wants to express a completed result:

• я бы приготовил котлеты = I would cook/make the cutlets (and they would be ready)

If you used готовил, that would be imperfective, which focuses more on the process or repeated activity:

• я бы готовил котлеты = I would be cooking cutlets / I would cook cutlets regularly

In this sentence, the speaker means a single completed action in response to a situation, so приготовил is the natural choice.

Here котлеты is in the accusative plural, because it is the direct object of приготовил.

The dictionary form is:

• котлета = cutlet

Plural:

• nominative plural: котлеты
• accusative plural: котлеты

For inanimate nouns, the accusative plural is usually the same as the nominative plural. So the form looks unchanged.

Compare:

• Я приготовил котлеты. = accusative plural
• Котлеты вкусные. = nominative plural

Same form, different function.

Both are possible, but they emphasize things slightly differently.

• котлеты из говядины = cutlets made from beef
• говяжьи котлеты = beef cutlets

The phrase из + genitive literally means made from / out of:

• суп из курицы = soup made from chicken
• сок из яблок = juice made from apples
• котлеты из говядины = cutlets made from beef

And yes, говяжьи котлеты is also perfectly natural. It is just a more adjective-based way to say the same basic thing.

Why говядины? Because из takes the genitive case:

• говядина → говядины

Because past tense verbs in Russian agree with the gender of the speaker/subject.

• я приготовил = I would have made / I would make — said by a man
• я приготовила = the same thing — said by a woman

So the sentence as written sounds like it is spoken by a male speaker.

This happens in all past tense forms in Russian:

• я был / я была
• я сделал / я сделала
• я приготовил / я приготовила

Its position is somewhat flexible, but not completely random.

In the main clause, all of these are possible:

• Я бы быстро приготовил котлеты.
• Я быстро бы приготовил котлеты.
• Я быстро приготовил бы котлеты.

The most natural version here is probably:

• я бы быстро приготовил котлеты

In the if-clause, если бы is a very standard combination:

• Если бы у нас не осталось плова...

So although бы can move around a bit, learners should treat если бы as a common fixed chunk and я бы приготовил as the safest default pattern.

Yes, absolutely. That would be a real future condition, not a hypothetical one.

Compare the two:

1. Если бы у нас не осталось плова, я бы быстро приготовил котлеты из говядины.
   = hypothetical / imagined / unreal

2. Если у нас не останется плова, я быстро приготовлю котлеты из говядины.
   = real future possibility

The difference is similar to:

• If we didn’t have any pilaf left, I would make beef cutlets. vs.
• If we don’t have any pilaf left, I’ll make beef cutlets.

So the grammar changes because the type of condition changes.

Russian word order is more flexible than English word order, because case endings carry much of the grammatical information.

The given sentence is fully natural:

• Если бы у нас не осталось плова, я бы быстро приготовил котлеты из говядины.

But you could rearrange parts for emphasis:

• Я бы быстро приготовил котлеты из говядины, если бы у нас не осталось плова.
• Если бы плова у нас не осталось, я бы быстро приготовил котлеты из говядины.

The meaning stays basically the same, but the emphasis shifts.

A good rule for learners:

• keep the original order unless you have a reason to emphasize something
• Russian allows flexibility, but natural phrasing still matters