Aunque la receta parece fácil, mi hermana sigue preguntando cuánta sal necesita y qué textura debe tener la salsa.

Aunque introduces a subordinate clause meaning although / even though. It connects the two ideas in a tighter way than pero.

• Aunque la receta parece fácil, ... = Although the recipe seems easy, ...
• ..., pero mi hermana sigue preguntando ... would also be possible, but it would be structured as two coordinated clauses instead of one concessive clause.

So aunque is the natural choice for although.

Parecer means to seem / to appear. It suggests appearance, not certainty.

• La receta parece fácil = it looks easy / it seems easy
• La receta es fácil = it is easy

So the speaker is saying the recipe looks easy, but that may not match reality.

After aunque, Spanish can use either the indicative or the subjunctive, depending on the meaning.

Here, parece is in the indicative because the speaker treats this as a real, accepted fact:

• Aunque la receta parece fácil... = the recipe does in fact seem easy

If the idea were hypothetical, unknown, or not accepted as real, the subjunctive could appear in other contexts.

This is the structure seguir + gerundio, which means to keep doing something or to continue doing something.

• sigue preguntando = she keeps asking / she continues asking

Other examples:

• Sigue hablando = He/She keeps talking
• Seguimos esperando = We’re still waiting

This is a very common Spanish structure.

Because sal is a feminine noun in Spanish: la sal.

So the question word must agree with it:

• cuánta sal = how much salt
• cuánto azúcar = how much sugar

Even though salt is uncountable in English, Spanish still makes the question word agree in gender and number with the noun it modifies.

It has an accent because it is being used as an interrogative word in an embedded question.

• cuánta sal necesita = how much salt it/she needs

Spanish adds written accents to question words such as:

• qué
• cuál
• cuánto / cuánta
• cómo
• cuándo
• dónde

This happens even in indirect questions, not only direct ones.

Use qué before a noun:

• qué textura
• qué color
• qué tamaño

Cuál usually stands alone or is used in structures like cuál de...:

• ¿Cuál prefieres?
• ¿Cuál de estas salsas te gusta más?

So here qué textura is correct because textura is the noun being modified.

For the same reason as cuánta: it is an interrogative word inside an indirect question.

• preguntando qué textura debe tener la salsa

Even though no question marks appear, the clause still contains the idea of a question, so qué keeps its accent.

Compare:

• No sé qué quiere. = I don’t know what he/she wants.
• La cosa que quiere... = the thing that he/she wants...

In the second example, que is a relative word, so it has no accent.

Because this is an indirect question, and the verb inside it normally stays in the indicative when it refers to a real information question.

• pregunta cuánta sal necesita
• pregunta qué textura debe tener la salsa

She is asking for actual information, so the indicative is natural.

English speakers sometimes expect the subjunctive after verbs like ask, but Spanish does not use the subjunctive here just because the clause depends on preguntar.

It is an omitted subject, which is very common in Spanish.

From context, it most naturally refers to the dish / recipe / sauce being prepared — essentially how much salt it needs.

Spanish often leaves out subject pronouns when the meaning is clear:

• necesita = it needs / she needs, depending on context

Here, context tells us it is not the sister who needs salt, but the food.

Both can mean must have / should have, but deber is often slightly more neutral or descriptive in this kind of context.

• qué textura debe tener la salsa = what texture the sauce should have / is supposed to have
• qué textura tiene que tener la salsa can sound a bit stronger or more obligatory

In recipes, instructions, and descriptions of the correct result, deber is very common.

Because after quantity expressions like cuánto / cuánta, Spanish usually uses the noun directly, without an article.

• cuánta sal
• cuánta agua
• cuánto tiempo

Using an article here would sound unnatural.

Spanish does not use do-support the way English does.

English:

• How much salt does it need?

Spanish:

• Cuánta sal necesita

The Spanish verb itself carries the necessary information, so no extra helper like does is needed.

This is true in both direct and indirect questions:

• ¿Cuánta sal necesita?
• No sé cuánta sal necesita.

Because the sentence begins with a subordinate clause introduced by aunque:

• Aunque la receta parece fácil, ...

In Spanish, when this kind of clause comes first, a comma is normally used before the main clause. It helps separate the introductory idea from the main statement.