Google Classroom provides us with the perfect way to do this quickly using the Question feature. This can be found when you are in a classroom group by clicking on the + button on the bottom right hand corner. Then click on 'Create Question'
If you are revising something from a few months ago for upcoming exams or you know that some students are going to struggle to answer the question you also have the ability to provide scaffolding by enabling students to see each others answers. (shown by red arrow). Obviously if you are wanting a clear idea of a students understanding you would switch this off.
Similarly it can be used as an Exit ticket prior to leaving class. If you are going to do this, it helps to have the question already done and saved as a draft. To do this create the question as normal and click on the blue arrow next to the blue ASK button. This will allow you to save as a draft. This will then be shown at the top of your stream and you can then click on it quickly to send towards the end of the lesson. It is a good idea to do this with at least 10mins to go in your lesson.
The most excellent part of this tool is that you can see who has and hasn't answered the question, which allows you to let students go who have completed it and encourage those who have not to complete it prior to leaving!