had breakfast, ate breakfast
Во сколько вы завтракали?
What time did you have breakfast?
Вы уже завтракали?
Have you had breakfast yet?
— Психо (1960)
Вы вообще завтракали?
Did you even have breakfast?
Однажды мы там завтракали.
We had breakfast there once.
— Могила светлячков (1988)
Вы завтракали сегодня утром?
Did you have breakfast this morning?