Перед тем как печь пирог, лучше раскатать тесто скалкой.

Перед тем как is a common Russian way to say before when what follows is an action.

• перед = before
• тем = that
• как = how / when

Together, перед тем как functions like a set expression meaning before doing something or before something happens.

A rough literal breakdown is something like before that, how..., but you should learn it as one chunk: перед тем как = before.

A close alternative is прежде чем:

• Перед тем как печь пирог...
• Прежде чем печь пирог...

Both are natural.

Because the sentence is talking about an action in a general way: before baking a pie.

Russian often uses the infinitive after expressions like перед тем как when the subject is general, omitted, or understood from context. This is very similar to English before baking a pie rather than before you bake a pie.

So:

• перед тем как печь пирог = before baking a pie
• перед тем как ты будешь печь пирог = before you bake a pie

The version with the infinitive is shorter and more neutral.

This is about verbal aspect.

• печь = imperfective
• испечь = perfective

Here, печь is used because the sentence refers to the activity of baking in general, as the next step in the process. The idea is: before starting the baking process, it is better to roll out the dough.

If you used испечь, the focus would be more on completing the pie as a finished result. In this context, that is less natural.

So:

• перед тем как печь пирог = before baking a pie
• перед тем как испечь пирог can exist, but it sounds more result-focused and is less natural here

Because the sentence recommends a completed action with a clear result: the dough should be rolled out before baking.

• раскатывать = imperfective, process / repeated action
• раскатать = perfective, one completed action

Here the important thing is not the process of rolling, but the finished result: the dough ends up rolled out.

That is why лучше раскатать тесто means it is better to roll out the dough in the sense of get it properly rolled out.

Here лучше means it is better to.

So:

• лучше раскатать тесто = it is better to roll out the dough

Russian often uses лучше + infinitive to give advice or make a recommendation. It does not mean strict necessity, just that this is the better thing to do.

Compare:

• лучше раскатать тесто = it’s better to roll out the dough
• надо раскатать тесто = you need to roll out the dough
• нужно раскатать тесто = it is necessary to roll out the dough

So лучше sounds like advice, not an order.

Both are direct objects, so they are in the accusative case.

However, for these nouns, the accusative looks the same as the nominative:

• пирог is masculine, inanimate
  nominative: пирог
  accusative: пирог

• тесто is neuter
  nominative: тесто
  accusative: тесто

That is why their forms do not change here.

You can see the structure like this:

• печь пирог = to bake a pie
• раскатать тесто = to roll out dough

Because скалкой is in the instrumental case.

The instrumental case is often used for the tool or means by which something is done.

So:

• скалка = a rolling pin
• скалкой = with a rolling pin

Therefore:

• раскатать тесто скалкой = to roll out the dough with a rolling pin

This is a very common use of the instrumental in Russian:

• писать ручкой = write with a pen
• резать ножом = cut with a knife
• есть вилкой = eat with a fork

Because this is a general piece of advice, not a sentence about one specific person.

Russian very often leaves out the subject when it is:

• obvious from context
• unimportant
• meant generally

This sentence is like English:

• Before baking a pie, it’s better to roll out the dough with a rolling pin.

English also does not name a specific person here.

If you wanted to make the subject explicit, you could say something like:

• Перед тем как печь пирог, вам лучше раскатать тесто скалкой. = Before baking a pie, you’d better roll out the dough with a rolling pin.

But the original version is more neutral and natural as general advice.

Because the opening part of the sentence is a subordinate clause or clause-like introductory phrase:

• Перед тем как печь пирог = before baking a pie

After that, the main clause begins:

• лучше раскатать тесто скалкой = it is better to roll out the dough with a rolling pin

Russian normally separates that opening dependent part from the main clause with a comma.

So the comma marks the boundary between:

• the before... part
• the main statement

Yes, Russian word order is flexible, but the given order is neutral and natural.

The sentence as written:

• Перед тем как печь пирог, лучше раскатать тесто скалкой.

This sounds like standard advice.

You could move things around for emphasis, for example:

• Тесто лучше раскатать скалкой перед тем, как печь пирог.
• Перед тем как печь пирог, тесто лучше раскатать скалкой.

These are also possible, but they shift the emphasis a bit.

The original version is a good default pattern:

1. time/background first
2. recommendation second
3. instrument last

Yes. Печь пирог is a completely normal way to say to bake a pie.

Russian often uses a simple verb + object structure here:

• печь хлеб = bake bread
• печь торт = bake a cake
• печь пирог = bake a pie

So there is nothing unusual about печь пирог in this sentence. It is standard Russian.