Learn Hardcore Greek: Η μαμά μου δεν είναι μάγειρας, αλλά το φαγητό της είναι πάντα νόστιμο. - My mom is not a cook, but her food is always tasty.

So Η μαμά μου is exactly like saying My mom in English.
If you said Η μητέρα μου, it would sound more formal, like My mother in careful or formal speech.

Why is it Η μαμά μου and not Η μου μαμά? Where does μου normally go?

In Greek, the unstressed possessive pronouns like μου, σου, του, της, μας, σας, τους usually go after the noun:

η μαμά μου = my mom
το βιβλίο σου = your book
το σπίτι μας = our house

So Η μου μαμά is incorrect in modern standard Greek.
If you want to emphasize the possessor, you use a different structure, for example:

η δική μου μαμά = my own mom (with emphasis on my)

In English we say She is not a cook, but in Greek there is no she. Why is there no subject pronoun?

Greek is a pro‑drop language, which means subject pronouns (I, you, he, she, we, etc.) are often left out when the subject is clear from context.

In Η μαμά μου δεν είναι μάγειρας, the subject is already clear: η μαμά μου (“my mom”). So there is no need to add αυτή (she).

You could say:

Αυτή, η μαμά μου, δεν είναι μάγειρας

but that would sound marked/emphatic, like stressing she, my mom specifically. In normal speech, you just use η μαμά μου without an extra she.

Why is the negative δεν placed before είναι? Could I use μην instead?

In modern Greek:

δεν is used with most indicative verbs, including είμαι (to be).
μην is used mainly with subjunctive (with να), imperative, and some other special cases.

So:

δεν είναι = is not (correct here)
μην είναι = used in contexts like so that it is not…, e.g. να μην είναι κρύο (so that it isn’t cold).

In this sentence you must say:

Η μαμά μου δεν είναι μάγειρας
not Η μαμά μου μην είναι μάγειρας (wrong in this context).

The word μάγειρας looks masculine. Is it strange to use it about μαμά (a woman)? Should it be μαγείρισσα?

μάγειρας is grammatically masculine, but it is often used as a profession noun that can refer to any gender, especially in everyday speech:

είναι μάγειρας = he/she is a cook (context tells you the gender)

There is also a specifically feminine form:

μαγείρισσα = female cook (used, but a bit less in modern professional contexts)

In your sentence:

Η μαμά μου δεν είναι μάγειρας

is completely natural and common. If you wanted to highlight that she’s a woman cook (in a context where that matters), you could say:

Η μαμά μου δεν είναι μαγείρισσα

Both are grammatically acceptable; μάγειρας sounds a bit more neutral/professional, μαγείρισσα more explicitly feminine/traditional.

What exactly does αλλά mean, and how is it different from other Greek words for but, like μα or όμως?

αλλά is the standard, neutral word for but in Greek, used in both speech and writing:

δεν είναι μάγειρας, αλλά το φαγητό της είναι πάντα νόστιμο
= she is not a cook, but her food is always tasty

Other options:

μα – also means but, a bit more informal/colloquial or expressive.
Δεν είναι μάγειρας, μα το φαγητό της είναι πάντα νόστιμο.
όμως – usually translates as however / though, and is more flexible in position:
Δεν είναι μάγειρας, όμως το φαγητό της είναι πάντα νόστιμο.

In your sentence, αλλά is the most neutral and textbook‑style choice.

Why is it το φαγητό της and not της φαγητό? What is the normal order for her food in Greek?

The normal pattern in Greek is:

article + noun + possessive pronoun

So you say:

το φαγητό της = her food
το σπίτι του = his house
η δουλειά μου = my job

Putting the possessive before the noun (της φαγητό) is ungrammatical in standard modern Greek.

If you want to emphasize, there is another form:

το δικό της φαγητό = her own food (with emphasis)

Why is it το φαγητό της and not το φαγητό της μαμάς μου? Are both correct?

Both are correct; they just feel a bit different:

το φαγητό της = her food
The owner (she) is already clear from context (we just mentioned η μαμά μου), so a simple της is natural.
το φαγητό της μαμάς μου = my mom’s food
This repeats who the owner is, so it gives a bit more emphasis or clarity, e.g. if there are several people involved.

In your sentence, το φαγητό της sounds smooth and natural because της clearly refers back to η μαμά μου in the first part.

Why is φαγητό used here, and what gender is it? How does that affect the rest of the sentence?

φαγητό means food / meal and is a neuter noun in Greek.

Article: το φαγητό (not η or ο)
So in the sentence: αλλά το φαγητό της είναι πάντα νόστιμο

Because φαγητό is neuter, any adjective that describes it must also be neuter singular:

νόστιμος (masculine)
νόστιμη (feminine)
νόστιμο (neuter)

So you must say:

το φαγητό της είναι νόστιμο (neuter with neuter)
not είναι νόστιμος / νόστιμη.

Why is the adjective νόστιμο in the neuter form? Couldn’t it be νόστιμη because μαμά is feminine?

The adjective always agrees with the noun it directly describes, not some earlier noun in the sentence.

Here, νόστιμο describes φαγητό (food), not μαμά:

το φαγητό → neuter singular → νόστιμο
η μαμά → feminine singular → would take νόστιμη if it were being described

Examples:

Η μαμά μου είναι νόστιμη.
This would literally mean My mom is tasty (and sounds weird in Greek, just like in English).
Το φαγητό της είναι νόστιμο.
Her food is tasty – correct and natural.

So νόστιμο is neuter because it agrees with φαγητό.

Where can πάντα go in this sentence? Is είναι πάντα νόστιμο the only correct order?

In your sentence:

το φαγητό της είναι πάντα νόστιμο

is the most common, neutral order. πάντα goes between the verb είναι and the adjective νόστιμο.

Other possible positions:

το φαγητό της πάντα είναι νόστιμο
Still correct; it can sound a bit more emphatic on “always”.

What you generally don’t do in this kind of sentence is put πάντα far away from the verb/adjective in a way that breaks the natural rhythm, for example:

✗ πάντα το φαγητό της είναι νόστιμο – possible in some contexts, but with a different emphasis (stressing always her food is tasty).

So for a learner, είναι πάντα νόστιμο is the safest and most natural pattern:
[subject] + είναι + πάντα + adjective.

Could we leave out the second είναι and say …αλλά το φαγητό της πάντα νόστιμο?

No, you need the verb είναι in the second clause as well. In this type of sentence, Greek does not normally drop the copula (the verb to be):

Δεν είναι μάγειρας, αλλά το φαγητό της είναι πάντα νόστιμο. ✅
✗ Δεν είναι μάγειρας, αλλά το φαγητό της πάντα νόστιμο. ❌

Each clause needs its own verb unless you’re in a very specific, usually poetic or headline‑style context, which this is not.