Si quieres, mañana encargo otra tarta pequeña y unas velas más para los niños.

Si quieres literally means if you want, but in this kind of sentence it often works like if you like or if you want me to.

At the start of the sentence, it softens the suggestion. The speaker is not just announcing a plan; they are checking whether the other person agrees.

So the tone is something like:

If you want, tomorrow I’ll order another small cake and some more candles for the children.

After si for a real, possible condition in the present or future, Spanish normally uses the present indicative, not the subjunctive.

So:

• Si quieres, mañana encargo... = If you want, tomorrow I’ll order...

This is a normal, open condition.

A subjunctive would not be used here. A different, more hypothetical version would be:

• Si quisieras, mañana encargaría... = If you wanted, I would order...

That sounds more tentative or hypothetical.

Spanish often leaves out subject pronouns when the verb ending already shows who the subject is.

Here, encargo clearly means I order / I’ll order, because the -o ending shows yo.

So:

• mañana encargo... = tomorrow I order / I’ll order

Adding yo is possible, but it is usually only done for emphasis, contrast, or clarity:

• Yo encargo la tarta, tú compras las bebidas.

Spanish, like English, often uses the present tense to talk about a near future action, especially when there is a time word like mañana.

So:

• Mañana encargo... literally looks like Tomorrow I order...
• But naturally it means Tomorrow I’ll order...

This is very common and natural.

You could also say:

• Mañana encargaré...

That is the simple future. It is also correct, but mañana encargo often sounds more immediate, planned, and conversational.

Here encargar means to order, to place an order for, or to ask for something to be prepared/reserved.

In Spain, this is very natural for things like cakes, food, or items you want a shop to get ready for you.

So encargo otra tarta suggests something like ordering another cake from a bakery or shop, not just buying one off the shelf.

This is slightly different from:

• comprar = to buy
• pedir = to ask for / order

In this context, encargar strongly suggests arranging it in advance.

Because otra already includes the idea of another or one more.

So:

• otra tarta = another cake / one more cake

You do not normally say una otra tarta.

This is similar to English: you say another cake, not one another cake.

In Spanish, most descriptive adjectives normally come after the noun.

So:

• tarta pequeña = small cake

This is the most neutral, standard order.

You may sometimes see an adjective before the noun, but that usually adds emphasis, style, or a slightly different nuance. In this sentence, otra tarta pequeña is the most natural everyday wording.

Both can work, but they are not exactly the same.

• unas velas más = a few more candles / some more candles
• más velas = more candles

In this sentence, unas velas más sounds very natural because the speaker means an additional small quantity, not just a general increase.

So it feels like:

• another small cake and a few more candles

The más comes after the noun phrase here because it means additional.

Unas is the plural indefinite article, roughly some or a few.

So:

• unas velas = some candles / a few candles

In English, we often leave this out, but in Spanish it is very common and natural to include it.

Here unas velas más sounds more complete and idiomatic than just velas más.

Also, in this birthday context, velas almost certainly means candles for the cake.

Grammatically, it comes right after unas velas más, so it most directly connects to that part. But in real conversation, it can easily be understood as the purpose of the whole plan: the extra cake and candles are for the children.

So the sentence can feel like:

• I’ll order another small cake and some more candles for the children

In many real contexts, listeners would naturally understand that the whole arrangement is for the children, not only the candles.

Yes. Spanish word order is flexible, especially with time expressions like mañana.

For example, these are all possible:

• Si quieres, mañana encargo otra tarta pequeña...
• Mañana, si quieres, encargo otra tarta pequeña...
• Encargo mañana otra tarta pequeña...

The original version sounds very natural. It starts with Si quieres to soften the statement, then gives the time mañana, and then the main action encargo.

So the order helps the sentence sound polite and conversational.