Learn Hardcore French: Je suis en train de préparer du riz avec un peu d'huile. - I am in the middle of preparing rice with a little oil.

It emphasizes that the action is happening right now, in progress. Both Je prépare du riz and Je suis en train de préparer du riz are correct; the latter is like English “I’m in the middle of preparing rice,” stronger than the plain present. It’s useful if you want to insist you’re busy at this very moment or to correct a misunderstanding. Otherwise, the simple present often suffices in French for “I’m doing X (now).”

Why is it en train de and not something like en train à?

Because it’s a fixed construction: être en train de + infinitive. The preposition is always de, and the verb that follows stays in the infinitive: Je suis en train de préparer… Never drop the de.

Why use préparer here? Could I say cuisiner, faire cuire, or faire instead?

préparer is broad: to prepare (which can include cooking).
cuisiner means to cook in general, often implying some actual cooking work; Je cuisine du riz is fine and common.
faire cuire focuses on the act of cooking/heating: Je fais cuire du riz is very idiomatic for rice.
faire alone is common in speech: Je fais du riz (“I’m making rice”). All are possible; choose based on the nuance you want (general prep vs the act of cooking).

Why is it du riz and not le riz or just bare riz?

du riz is the partitive (“some rice”), used for an unspecified amount of a mass noun.
le riz means “the rice” (specific rice already known or rice as a general category: Le riz est cher).
Bare nouns aren’t normally used as direct objects in French; you need an article. So you can’t say just Je prépare riz.

What exactly is du in du riz?

Formally, it’s the contraction of de + le. Functionally, it’s the masculine singular partitive article, used with mass nouns. The pattern is:

du (de + le): du pain, du riz
de la: de la confiture
de l’ (before vowel or mute h): de l’eau, de l’huile
des (plural “some”): des pâtes

How would I say this in the negative?

Two common options:

Keep the progressive: Je ne suis pas en train de préparer du riz.
Simple present with partitive change: Je ne prépare pas de riz. (After negation, partitives often become de/d’.) Note the negation surrounds suis (the conjugated verb): Je ne suis pas en train de…

Why is it un peu d’huile instead of un peu de l’huile?

With quantity expressions like un peu, you normally use de + noun without an article for a non-specific amount: un peu d’huile = “a little oil.”
Use un peu de l’huile only if you mean “a little of the oil” (a specific oil already identified: e.g., un peu de l’huile que tu as achetée).

So can I ever say un peu du/de la/de l’?

Yes, when you mean “a little of the [specific] …”:

un peu du riz que tu as cuit = a little of the rice you cooked
un peu de la soupe d’hier = a little of yesterday’s soup
un peu de l’huile d’olive de Provence = a little of that particular olive oil Without that specificity, stick to un peu de + noun.

Why the apostrophe in d’huile?

It’s elision: de becomes d’ before a word starting with a vowel sound or a mute h. huile begins with a vowel sound (the h is mute), so it’s d’huile. Compare:

d’eau, d’alcool, d’huile
but no elision with an aspirated h: de hamburger, not d’hamburger

Could I say avec de l’huile instead of avec un peu d’huile?

Yes. avec de l’huile = “with some oil” (no comment on quantity). avec un peu d’huile highlights that it’s only a small amount. You can also say things like avec un filet d’huile (“with a drizzle of oil”).

How do I replace du riz or de l’huile with pronouns?

Use en for nouns introduced by de or a partitive.

Without the progressive:
– Tu prépares du riz ? — Oui, j’en prépare.
– Tu utilises de l’huile ? — Oui, j’en utilise (un peu).
With en train de, the pronoun goes before the infinitive it belongs to:
– Je suis en train d’en préparer. (en = du riz)
– Je suis en train d’en utiliser un peu. (en = de l’huile) Avoid “J’en suis en train de préparer,” which sounds awkward.

Can I move avec un peu d’huile elsewhere in the sentence?

Yes. Word order is flexible for such complements:

Je prépare du riz avec un peu d’huile.
Avec un peu d’huile, je prépare du riz.
Je suis en train de préparer, avec un peu d’huile, du riz. (the commas add a slight pause/style)

Any quick pronunciation tips for this sentence?

riz = /ʁi/ (French guttural r, like a voiced uvular fricative)
huile = /ɥil/ (the /ɥ/ glide is like saying “wee” with rounded lips)
Je suis en often has a liaison: /ʒə sɥi zɑ̃/
en train de = /ɑ̃ tʁɛ̃ də/; the nasal vowels in en and train are key
In d’huile, the d links right into the /ɥ/: /dɥil/

What are the genders of riz and huile, and does that matter here?

riz is masculine (hence du riz in the partitive).
huile is feminine, but because it starts with a vowel sound, you see de l’huile (not de la huile).
Gender will matter if you add adjectives: une bonne huile, un riz parfumé.

Could I say something like Je prépare du riz à l’huile?

You can, but it slightly changes the nuance. à l’huile often describes a style or characteristic (“oil-based,” “in oil”), like sardines à l’huile. In your sentence, avec un peu d’huile simply states you’re adding a little oil while preparing the rice, which is the most natural phrasing for this context.