This is one of the Mexicanest (is that a word?) ways to order food!
It literally means: It’s going to be…
But in practice it works like:
👉 I’ll have…
You’ll hear it ALL the time at taquerías, restaurants, cafés, etc.
💡 You can use va a ser pretty much whenever you’re being served directly (i.e., when someone’s taking your order).
It’s NOT as common at busy food stands when you’re having to shout your order at the taquero (me das or te encargo rule the roost here!).
🌪️ When to whip it out
Whenever you’re ordering food and drink:
Va a ser una orden de pastor, por favor.
I’ll have an order of pastor, please.
Va a ser un agua de jamaica, porfa.
I’ll take a hibiscus agua fresca, please.
Va a ser la grande, por favor.
I’ll go with the large one, please.
Van a ser dos americanos.
I’ll have two americanos.
You'll also hear it when being told how much you owe: