Kerf Mount Corner Brackets are great. But it takes some thinking if you are working with larger lumber. I recently purchased these and these from amazon.
The corner bracket looks like this:
The trick is figuring out where to cut the leg at 45 degrees and the kerfs, especially if the leg isn’t square. I was going to work out the geometry of this, but instead I measured the bracket, drew a horizontal profile in visio and then measured the geometry. Since the leg isn’t square, I had to decide where the bracket mounts flush. I included my drawing here in the hopes that it may be helpful to you.
There are instructions here.