お昼に

at lunchtime

→ 御昼
phrase Uncommon #14,576
at lunchtime お昼 means “noon” or “lunchtime,” and に marks the time when something happens. Depending on context, it can also mean “by lunchtime,” especially with は, as in お昼には戻るから.
JA: お昼に一緒にご飯を食べませんか?
EN: Would you like to have lunch together?

お昼に何が食べたい

What do you want to eat for lunch?

お昼に迎えにいくから

I'll come pick you up around noon.

母はお昼に私が食べたいものを出してくれた

My mother made what I wanted to eat for lunch.

今日のお昼に何を食べましたか

What did you eat for lunch today?

お昼にしましょう

Let's have lunch.

— アイム・スティル・ヒア (2024)

お昼にトムのところへ行ってもいいでしょうか

May I go to Tom’s place for lunch?

お昼に

At lunchtime.

お昼に呼ぶわね

I'll call you at lunchtime.

— Hoje Eu Quero Voltar Sozinho (2014)

お昼にしない

Shall we have lunch?

— 天気の子 (2019)

お昼に戻るから

I’ll be back by lunchtime.

— ウィッチ (2016)

お昼に

For lunch?

— フォーリング・ダウン (1993)

さてお昼にしましょう

Well, let's have lunch.

お昼にしよう

Let's have lunch.