SQL Query slow beginning of each day

I have a basic query below.

Select [ID] FROM MyTable Where [TextBlobField] like '%test%'

This query takes a long time when I first run it each day. After that it only takes about 5 seconds. Next morning back to long query time. Is this because SQL is caching a index temporary?

How can I make this fast all the time? NOTE: I do not have permission to create my own index on the table. I can create a Stored Procedure... but don't know if that help? Should I create a view?