Pre-requisite: You have to know your last commit message from your deleted branch.
git reflog
Search for message in the list:
a901eda HEAD@{18}: commit: <last commit message>
Now you have two options, either checkout revision or HEAD
git checkout a901eda
# or
git checkout HEAD@{18}
Create branch
git branch recovered-branch
You may want to push that back to remote
git push origin recovered-branch:recovered-branch